Add support for publishing pre-release version

Author: wch

.github/workflows/publish.yml

@@ -4,6 +4,7 @@ on:
       - "v[0-9]*"
     branches:
       - "main"
+      - "v[0-9]*-pre*" # Add support for pre-release branches
   pull_request:
     branches:
       - "main"
@@ -26,6 +27,15 @@ jobs:
       - name: Build Extension
         run: npm run vsix
 
+      - name: Check if pre-release
+        id: check_prerelease
+        run: |
+          if [[ ${{ github.ref }} =~ .*-pre.* ]]; then
+            echo "is_prerelease=true" >> $GITHUB_OUTPUT
+          else
+            echo "is_prerelease=false" >> $GITHUB_OUTPUT
+          fi
+
       - name: Upload extension to Actions Artifact
         uses: actions/upload-artifact@v4
         with:
@@ -48,11 +58,21 @@ jobs:
 
       - run: npm ci
 
+      - name: Check if pre-release
+        id: check_prerelease
+        run: |
+          if [[ ${{ github.ref }} =~ .*-pre.* ]]; then
+            echo "is_prerelease=true" >> $GITHUB_OUTPUT
+          else
+            echo "is_prerelease=false" >> $GITHUB_OUTPUT
+          fi
+
       - name: Publish to Open VSX Registry
         uses: HaaLeo/publish-vscode-extension@v1
         with:
           pat: ${{ secrets.OPEN_VSX_TOKEN }}
           skipDuplicate: true
+          preRelease: ${{ steps.check_prerelease.outputs.is_prerelease }}
 
   publish-vscode-marketplace:
     runs-on: ubuntu-latest
@@ -70,9 +90,19 @@ jobs:
 
       - run: npm ci
 
+      - name: Check if pre-release
+        id: check_prerelease
+        run: |
+          if [[ ${{ github.ref }} =~ .*-pre.* ]]; then
+            echo "is_prerelease=true" >> $GITHUB_OUTPUT
+          else
+            echo "is_prerelease=false" >> $GITHUB_OUTPUT
+          fi
+
       - name: Publish to Visual Studio Marketplace
         uses: HaaLeo/publish-vscode-extension@v1
         with:
           pat: ${{ secrets.VSCE_PAT }}
           skipDuplicate: true
           registryUrl: https://marketplace.visualstudio.com
+          preRelease: ${{ steps.check_prerelease.outputs.is_prerelease }}