ci: electron example should not build with top level yarn build (#1195)

<!-- CURSOR_SUMMARY -->
> [!NOTE]
> **Low Risk**
> Low risk CI refactor plus removal of an example-only `build` script;
main impact is on the GitHub Actions e2e job behavior and environment
variable/secrets setup.
> 
> **Overview**
> Refactors `.github/workflows/electron.yaml`’s `run-example` job to
call the shared `./actions/run-example` composite action instead of
inlining dependency install/build, Xvfb/Playwright setup, and test
execution.
> 
> Enhances `actions/run-example/action.yml` to support an `env_vars`
input (written to `$GITHUB_ENV`) and to fetch the mobile SDK key in
addition to the existing client-side and flag keys; the Electron
workflow now supplies `DISPLAY`/`ELECTRON_DISABLE_SANDBOX` and moves
Xvfb/Playwright/startup into `before_test`.
> 
> Removes the `build` script from
`packages/sdk/electron/example/package.json`, so the example no longer
exposes a top-level `yarn build` entry point.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
7790739. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

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Author: joker23

.github/workflows/electron.yaml

@@ -81,32 +81,15 @@ jobs:
       - uses: actions/setup-node@53b83947a5a98c8d113130e565377fae1a50d02f # v6.3.0
         with:
           node-version: 24
-      - name: Install dependencies
-        run: yarn workspaces focus @internal/electron-example
-      - name: Build SDK dependencies
-        run: yarn workspaces foreach -pR --topological-dev --from '@internal/electron-example' run build
-      - name: Build example app
-        env:
-          ELECTRON_DISABLE_SANDBOX: '1'
-        run: yarn workspace @internal/electron-example build
-      - name: Setup Xvfb
-        run: |
-          sudo apt-get install -y xvfb
-          Xvfb :99 -screen 0 1024x768x24 > /tmp/xvfb.log 2>&1 &
-      - name: Install Playwright dependencies
-        run: yarn workspace @internal/electron-example playwright install --with-deps chromium
-      - uses: launchdarkly/gh-actions/actions/release-secrets@bbbbbda684f500766264e7fe327668094ba83d1c # release-secrets-v1.2.0
-        name: 'Get the mobile SDK key'
+      - uses: ./actions/run-example
         with:
+          workspace_name: '@internal/electron-example'
           aws_assume_role: ${{ vars.AWS_ROLE_ARN }}
-          ssm_parameter_pairs: '/sdk/common/hello-apps/mobile-key = LAUNCHDARKLY_MOBILE_KEY'
-      - uses: launchdarkly/gh-actions/actions/release-secrets@bbbbbda684f500766264e7fe327668094ba83d1c # release-secrets-v1.2.0
-        name: 'Get the test feature flag key'
-        with:
-          aws_assume_role: ${{ vars.AWS_ROLE_ARN  }}
-          ssm_parameter_pairs: '/sdk/common/hello-apps/boolean-flag-key = LAUNCHDARKLY_FLAG_KEY'
-      - name: Run e2e tests
-        env:
-          ELECTRON_DISABLE_SANDBOX: '1'
-          DISPLAY: ':99'
-        run: yarn workspace @internal/electron-example test
+          env_vars: |
+            DISPLAY=:99
+            ELECTRON_DISABLE_SANDBOX=1
+          before_test: |
+            sudo apt-get install -y xvfb
+            Xvfb :99 -screen 0 1024x768x24 > /tmp/xvfb.log 2>&1 &
+            yarn workspace @internal/electron-example playwright install --with-deps chromium
+            yarn workspace @internal/electron-example start -- --build

actions/run-example/action.yml

@@ -11,19 +11,34 @@ inputs:
   before_test:
     description: 'Shell commands to run before the e2e test step (e.g. install Playwright browsers)'
     default: ''
+  env_vars:
+    description: 'Newline-separated KEY=VALUE pairs to set as environment variables for all subsequent steps'
+    default: ''
 runs:
   using: composite
   steps:
     - name: Install dependencies
       shell: bash
       run: yarn workspaces focus ${{ inputs.workspace_name }}
 
+    - name: Set environment variables
+      shell: bash
+      if: ${{ inputs.env_vars != '' }}
+      run: |
+        echo "${{ inputs.env_vars }}" >> $GITHUB_ENV
+
     - uses: launchdarkly/gh-actions/actions/release-secrets@1a3dc56945c8e87bc952119b055f9481b4d642b0
       name: 'Get the client-side SDK key'
       with:
         aws_assume_role: ${{ inputs.aws_assume_role }}
         ssm_parameter_pairs: '/sdk/common/hello-apps/client-key = LAUNCHDARKLY_CLIENT_SIDE_ID'
 
+    - uses: launchdarkly/gh-actions/actions/release-secrets@1a3dc56945c8e87bc952119b055f9481b4d642b0
+      name: 'Get the mobile SDK key'
+      with:
+        aws_assume_role: ${{ inputs.aws_assume_role }}
+        ssm_parameter_pairs: '/sdk/common/hello-apps/mobile-key = LAUNCHDARKLY_MOBILE_KEY'
+
     - uses: launchdarkly/gh-actions/actions/release-secrets@1a3dc56945c8e87bc952119b055f9481b4d642b0
       name: 'Get the test feature flag key'
       with:

packages/sdk/electron/example/package.json

@@ -7,7 +7,6 @@
   "private": true,
   "scripts": {
     "start": "electron-forge start",
-    "build": "electron-forge start -- --build",
     "test": "playwright test",
     "clean": "electron-forge clean",
     "package": "electron-forge package",