GLSP-1636: Migrate to pnpm

- Migrate package manager from yarn + lerna to pnpm, using built-in
  workspace management and the workspace:* protocol for intra-repo deps
- Replace lerna publish with the glsp releng publish command
- Add pnpm-workspace.yaml: public-hoist dev tooling, gate third-party
  deps via minimumReleaseAge, allow Playwright build scripts, and
  override vulnerable transitive deps (serialize-javascript, js-yaml,
  diff) flagged by pnpm audit
- Declare dependencies that pnpm's strict layout no longer hoists
  (reflect-metadata, playwright-core, ts-dedent) and scope the
  reflect-metadata typings to the package that uses them
- Update CI workflows to set up and cache pnpm and build explicitly
- Consolidate validation into a single /fix skill (drop /verify) and
  refresh CLAUDE.md, AGENTS.md, and docs accordingly

Also:
- Pull the latest @eclipse-glsp/* next dependencies
- Reformat files picked up by the updated prettier config

Part of: eclipse-glsp/glsp#1636

Author: tortmayr

.claude/skills/fix/SKILL.md

@@ -1,12 +1,26 @@
 ---
 name: fix
-description: Auto-fix all lint, formatting, and copyright header issues across the workspace. Use when validation (`/verify`) fails or when explicitly requested.
+description: Run the fix-and-verify suite for the workspace (compile, auto-fix lint/format/headers). IMPORTANT - Proactively invoke this skill after completing any code changes (new features, bug fixes, refactors) before reporting completion. Re-run it after manually addressing anything it could not auto-fix.
 ---
 
-Run the full auto-fix suite for this project from the repository root:
+Run the auto-fix and validation suite for the GLSP Playwright monorepo from the repository root.
+
+1. Build first. This is a hard gate: if the build fails, stop immediately, report the build errors, and do not run any of the following steps. The build must pass before anything else runs.
+
+```bash
+pnpm build
+```
+
+2. Auto-fix lint, formatting, and copyright headers. Run all three even if an earlier one reports remaining problems (they are independent):
 
 ```bash
-yarn fix:all
+pnpm lint:fix
+pnpm format
+pnpm headers:fix
 ```
 
-After fixing, report what changed. If any issues remain that couldn't be auto-fixed, list them and suggest manual fixes.
+Then:
+
+- If `pnpm build` failed, fix the compile errors and re-run this skill.
+- If `pnpm lint:fix` reported lint errors it could not fix, address them manually and re-run this skill.
+- Otherwise everything is clean (compile succeeds, formatting and headers are corrected in place, lint has no remaining errors) — report completion.

.claude/skills/generate-changelog/SKILL.md

@@ -8,6 +8,7 @@ description: Generate changelog entries from merged PRs since the last release.
 Generate changelog entries by analyzing merged PRs since the last release.
 
 Execute these phases in order:
+
 1. **Data Gathering** — find last release, fetch PRs, classify, generate entries
 2. **Changelog Update** — write entries into CHANGELOG.md
 3. **Review & Approval** — present the actual diff to the user for review
@@ -20,11 +21,13 @@ Execute these phases in order:
 ### Step 1.1: Find the latest release tag
 
 Run:
+
 ```bash
 git tag --sort=-creatordate | grep -E '^v[0-9]+\.[0-9]+\.[0-9]+$' | head -1
 ```
 
 Record as `LAST_TAG`. Get the tag's date:
+
 ```bash
 git log -1 --format=%aI $LAST_TAG
 ```
@@ -46,12 +49,13 @@ Use the date portion only from `TAG_DATE` (e.g. `2026-02-09`).
 ### Step 1.4: Filter PRs
 
 **Skip rules** (in order):
+
 1. PR has the `changelog` label → skip (already tracked in a previous changelog update)
 2. Author login is `dependabot` or `dependabot[bot]` → skip
 3. Title matches version bump patterns → skip:
-   - Starts with `Switch to` and contains `-next`
-   - Title is a bare version like `vX.Y.Z`
-   - Title starts with `Release v`
+    - Starts with `Switch to` and contains `-next`
+    - Title is a bare version like `vX.Y.Z`
+    - Title starts with `Release v`
 4. Title contains `update changelog` (case insensitive) → skip
 5. Title is purely CI/metadata (readme badges, workflow config) AND body does NOT contain `[x] This PR should be mentioned in the changelog` → skip
 
@@ -62,9 +66,9 @@ Use the date portion only from `TAG_DATE` (e.g. `2026-02-09`).
 1. If body contains `[x] This PR introduces a breaking change` → **breaking**
 2. If body contains `[ ] This PR introduces a breaking change` → **normal**
 3. If no checkbox info, analyze title and body:
-   - Breaking keywords: "refactor", "rename", "remove", "replace", "migrate", "breaking", "deprecate"
-   - Clearly non-breaking (bug fix, docs, minor enhancement) → **normal**
-   - Uncertain → flag for user review
+    - Breaking keywords: "refactor", "rename", "remove", "replace", "migrate", "breaking", "deprecate"
+    - Clearly non-breaking (bug fix, docs, minor enhancement) → **normal**
+    - Uncertain → flag for user review
 
 ### Step 1.6: Assign category tags
 
@@ -75,25 +79,29 @@ Pick the most fitting tag from the vocabulary (Step 1.2) based on PR title and b
 #### Entry Format
 
 **Normal changes:**
+
 ```
 -   [tag] Description [#N](https://github.com/eclipse-glsp/glsp-playwright/pull/N)
 ```
 
 **Breaking changes** with migration sub-items:
+
 ```
 -   [tag] Description [#N](https://github.com/eclipse-glsp/glsp-playwright/pull/N)
     -   Migration detail 1
     -   Migration detail 2
 ```
 
 **Multiple PRs for the same change:**
+
 ```
 -   [tag] Description [#N](url) [#M](url)
 ```
 
 #### Style Guide
 
 **Formatting:**
+
 - Entry prefix: `-   ` (dash + exactly 3 spaces)
 - Sub-item indent: 4 spaces + `-   ` (4 spaces from parent dash)
 - Sub-sub-item indent: 8 spaces + `-   `
@@ -102,6 +110,7 @@ Pick the most fitting tag from the vocabulary (Step 1.2) based on PR title and b
 - PR links are mandatory, full URLs: `[#123](https://github.com/eclipse-glsp/glsp-playwright/pull/123)`
 
 **Wording:**
+
 - Always start with a **present tense imperative verb** (not past tense)
 - Common verbs: Fix, Improve, Add, Update, Extend, Ensure, Introduce, Remove, Refactor, Rename, Provide, Allow, Support
 - **Bug fixes**: "Fix a bug that caused/prevented...", "Fix X behavior"
@@ -111,19 +120,22 @@ Pick the most fitting tag from the vocabulary (Step 1.2) based on PR title and b
 - Be specific — never "Fix various issues"
 
 **Capitalization:**
+
 - Tags are always lowercase: `[diagram]`, not `[Diagram]`
 - Description starts lowercase after the tag (unless proper noun or code element)
 - Section headers: Title Case (`### Potentially Breaking Changes`)
 
 **Description cleanup from PR title:**
+
 - Remove issue tracker prefixes (e.g. `GLSP-1234:`, `GH-123:`, `ISSUE-456:`)
 - Remove conventional commit prefixes: `fix:`, `feat:`, `chore:`
 - Rephrase bug-report style to changelog style:
-  - BAD: "Edit label UI does not resize on graph zoom"
-  - GOOD: "Fix edit label UI not resizing on graph zoom"
+    - BAD: "Edit label UI does not resize on graph zoom"
+    - GOOD: "Fix edit label UI not resizing on graph zoom"
 - Keep concise — one line
 
 **Breaking changes:**
+
 - Describe what changed, why it's breaking, and how to migrate
 - Extract migration sub-items from the PR body's "What it does" section
 
@@ -136,11 +148,13 @@ Pick the most fitting tag from the vocabulary (Step 1.2) based on PR title and b
 Read `CHANGELOG.md` in the repository root.
 
 **Active section detection:**
+
 - An active section has the `- active` suffix (e.g. `## v2.7.0 - active`)
 - If an active section exists → merge new entries into it
 - If the topmost section is a released version (no `- active` suffix) → create a new active section above it
 
 **Creating a new section:**
+
 - Bump the minor version of `LAST_TAG` (e.g. `v2.6.0` → `v2.7.0`)
 - Insert after the title line, before the first `## ` heading:
 
@@ -149,17 +163,18 @@ Read `CHANGELOG.md` in the repository root.
 
 ### Changes
 
--   [tag] Entry [#N](url)
+- [tag] Entry [#N](url)
 
 ### Potentially Breaking Changes
 
--   [tag] Entry [#N](url)
-    -   Sub-item detail
+- [tag] Entry [#N](url)
+    - Sub-item detail
 ```
 
 Only include "Potentially Breaking Changes" if there are breaking entries.
 
 **Merging into existing active section:**
+
 - Check PR numbers against existing entries to avoid duplicates
 - Append new entries to the appropriate subsection
 - Create missing subsections as needed
@@ -185,6 +200,7 @@ Present the diff to the user.
 List any entries flagged as uncertain (category or breaking status) and ask the user to resolve them.
 
 Even if nothing is uncertain, ask:
+
 > "Does everything look correct, or would you like to adjust any entries?"
 
 ### Step 3.3: Collect user feedback
@@ -200,11 +216,13 @@ Even if nothing is uncertain, ask:
 ## Phase 4: PR Creation (Optional)
 
 Only execute this phase if the user explicitly requests a PR (either in their initial prompt or after reviewing the changelog). If the user hasn't mentioned a PR, ask after approval:
+
 > "Would you like me to create a PR for this changelog update, or are you done?"
 
 ### Step 4.1: Determine the branch name
 
 Check if `changelog-update` exists on remote:
+
 ```bash
 git ls-remote --heads origin changelog-update
 ```
@@ -229,6 +247,7 @@ Report the PR URL.
 ### Step 4.4: Label referenced PRs
 
 Add the `changelog` label to every PR mentioned in the new entries:
+
 ```bash
 gh pr edit PR_NUMBER --add-label "changelog"
 ```

.claude/skills/test/SKILL.md

@@ -17,7 +17,7 @@ If `$ARGUMENTS` contains a specific test name pattern, run tests filtered by tha
 Always run the setup script unless the user explicitly says to skip it:
 
 ```bash
-yarn repo:setup
+pnpm repo:setup
 ```
 
 This will clone and build the required GLSP repositories and generate the `.env` file from `.env.example`.
@@ -27,19 +27,19 @@ This will clone and build the required GLSP repositories and generate the `.env`
 Ensure the project is compiled:
 
 ```bash
-yarn
+pnpm build
 ```
 
 ### 3. Run Tests
 
 Run the appropriate test command:
 
--   **all** (default, no argument): `yarn test` (runs all integrations)
--   **standalone**: `yarn test:standalone`
--   **standalone-browser**: `yarn test:standalone-browser`
--   **theia**: `yarn test:theia`
--   **vscode**: `yarn test:vscode`
--   **pattern match**: If `$ARGUMENTS` contains a specific test name pattern, run: `cd examples/workflow-test && yarn playwright test -g "$ARGUMENTS"`
+- **all** (default, no argument): `pnpm test` (runs all integrations)
+- **standalone**: `pnpm test:standalone`
+- **standalone-browser**: `pnpm test:standalone-browser`
+- **theia**: `pnpm test:theia`
+- **vscode**: `pnpm test:vscode`
+- **pattern match**: If `$ARGUMENTS` contains a specific test name pattern, run: `cd examples/workflow-test && pnpm playwright test -g "$ARGUMENTS"`
 
 ### 4. Report Failures
 

.claude/skills/verify/SKILL.md

@@ -25,5 +25,5 @@ to learn how to report vulnerabilities.
 
 <!-- Please check, when if it applies to your change. -->
 
--   [ ] This PR should be mentioned in the changelog
--   [ ] This PR introduces a breaking change (if yes, provide more details below for the changelog and the migration guide)
+- [ ] This PR should be mentioned in the changelog
+- [ ] This PR introduces a breaking change (if yes, provide more details below for the changelog and the migration guide)

.github/PULL_REQUEST_TEMPLATE.md

@@ -24,33 +24,27 @@ jobs:
     timeout-minutes: 60
     steps:
       - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+      - uses: pnpm/action-setup@0e279bb959325dab635dd2c09392533439d90093 # v6.0.8
       - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
         with:
           node-version: 22.x
-      - name: Install dependencies
-        run: yarn install
-      - name: Check for uncommitted changes in yarn.lock
-        run: |
-          if git diff --name-only | grep -q "^yarn.lock"; then
-            echo "::error::The yarn.lock file has uncommitted changes!"
-            exit 1
-          fi
+          cache: pnpm
+      - name: Build
+        run: pnpm build
   lint:
     name: Lint
     timeout-minutes: 60
     runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+      - uses: pnpm/action-setup@0e279bb959325dab635dd2c09392533439d90093 # v6.0.8
       - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
         with:
           node-version: 22.x
-      - name: Install
-        run: |
-          yarn install --ignore-scripts
-          yarn compile
+          cache: pnpm
       - name: Create eslint json report
         run: |
-          yarn lint:ci
+          pnpm lint:ci
         continue-on-error: true
       - name: Create summary
         run: |
@@ -67,18 +61,20 @@ jobs:
         integration: [standalone, theia, vscode]
     steps:
       - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+      - uses: pnpm/action-setup@0e279bb959325dab635dd2c09392533439d90093 # v6.0.8
       - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
         with:
           node-version: '22'
-      - name: Install dependencies
-        run: yarn install
+          cache: pnpm
+      - name: Build
+        run: pnpm build
       - name: Prepare repos
-        run: yarn repo:setup --${{ matrix.integration }}
+        run: pnpm repo:setup --${{ matrix.integration }}
         env:
           GH_TOKEN: ${{ github.token }}
       - name: Run Playwright tests
         id: run_playwright_tests
-        run: xvfb-run -a yarn test
+        run: xvfb-run -a pnpm test
       - name: Upload Playwright report
         if: ${{ always() }}
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
@@ -96,23 +92,25 @@ jobs:
         integration: [standalone, theia, vscode]
     steps:
       - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+      - uses: pnpm/action-setup@0e279bb959325dab635dd2c09392533439d90093 # v6.0.8
       - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
         with:
           node-version: '22'
+          cache: pnpm
       - name: Set up JDK
         uses: actions/setup-java@be666c2fcd27ec809703dec50e508c2fdc7f6654 # v5.2.0
         with:
           distribution: 'temurin'
           java-version: '21'
-      - name: Install dependencies
-        run: yarn install
+      - name: Build
+        run: pnpm build
       - name: Prepare repos
-        run: yarn repo:setup --${{ matrix.integration }} --java
+        run: pnpm repo:setup --${{ matrix.integration }} --java
         env:
           GH_TOKEN: ${{ github.token }}
       - name: Run Playwright tests
         id: run_playwright_tests
-        run: xvfb-run -a yarn test
+        run: xvfb-run -a pnpm test
       - name: Upload Playwright report
         if: ${{ always() }}
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1

.github/workflows/ci.yml

@@ -20,22 +20,24 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+      - uses: pnpm/action-setup@0e279bb959325dab635dd2c09392533439d90093 # v6.0.8
       - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
         with:
           node-version: '22'
-      - name: Install dependencies
-        run: yarn install
+          cache: pnpm
+      - name: Build
+        run: pnpm build
       - name: Prepare repos
-        run: yarn repo:setup
+        run: pnpm repo:setup
         env:
           GH_TOKEN: ${{ github.token }}
       - name: Run Playwright tests
         id: run_playwright_tests
         run: |
           if [ ${{ matrix.os }} == 'ubuntu-latest' ]; then
-            xvfb-run -a yarn test
+            xvfb-run -a pnpm test
           else
-             yarn test
+             pnpm test
           fi
       - name: Upload Playwright report
         if: ${{ always() }}