Add automated publishing to Open VSX Registry

.github/workflows/release-please.yml

@@ -49,17 +49,21 @@ jobs:
       - uses: actions/checkout@v4
         with:
           ref: ${{ steps.event_details.outputs.tag_name }}
+      # Publishes to GitHub releases, VS Code Marketplace, and Open VSX Registry
+      # Requires secrets: PAT_VSCE (VS Code Marketplace) and OVSX_PAT (Open VSX)
       - name: Add files and publish release
         env:
           GITHUB_TOKEN: ${{ github.token }}
           VSCE_PAT: ${{ secrets.PAT_VSCE }}
+          OVSX_PAT: ${{ secrets.OVSX_PAT }}
           TAG_NAME: ${{ steps.event_details.outputs.tag_name }}
         run: |
           npm ci
           npm run package
           mv wit-idl.vsix ${TAG_NAME}.vsix
           gh release upload ${TAG_NAME} ${TAG_NAME}.vsix
           npx vsce publish --packagePath ${TAG_NAME}.vsix
+          npx ovsx publish ${TAG_NAME}.vsix -p ${OVSX_PAT}
 
   label:
     needs: [publish]
@@ -94,5 +98,7 @@ jobs:
 
             The release is available on:
             - GitHub releases: {release_link}
+            - Visual Studio Marketplace: https://marketplace.visualstudio.com/items?itemName=bytecodealliance.wit-idl
+            - Open VSX Registry: https://open-vsx.org/extension/bytecodealliance/wit-idl
 
             Your **[release-please](https://github.com/googleapis/release-please)** bot :rocket::pray:

README.md

@@ -68,6 +68,18 @@ Easily access extension features through the Command Palette:
 
 ## Installation
 
+### From Marketplace
+
+This extension is available on:
+
+- **Visual Studio Marketplace**: For VS Code users
+  - Install directly from VS Code: Search for "WIT IDL" in the Extensions view
+  - Or visit: https://marketplace.visualstudio.com/items?itemName=bytecodealliance.wit-idl
+
+- **Open VSX Registry**: For VSCodium and other compatible editors
+  - Install from Open VSX: https://open-vsx.org/extension/bytecodealliance/wit-idl
+  - Or install via CLI: `ovsx get bytecodealliance.wit-idl`
+
 ### Prerequisites
 
 This extension includes a WebAssembly component that requires the following tools for building:
@@ -91,3 +103,16 @@ To install from source, follow these steps:
 * Install build dependencies: `npm run setup-wasm`
 * Run npm commands to install:
 `npm ci && npm run install-extension`
+
+## Publishing (for maintainers)
+
+This extension is automatically published to both Visual Studio Marketplace and Open VSX Registry through GitHub Actions when a release is created.
+
+**Required secrets:**
+- `PAT_VSCE`: Personal Access Token for Visual Studio Marketplace
+- `OVSX_PAT`: Personal Access Token for Open VSX Registry
+
+To obtain an Open VSX token:
+1. Create an account at https://open-vsx.org/
+2. Generate a Personal Access Token from your account settings
+3. Add the token as `OVSX_PAT` in the repository secrets