Split CI workflows into per-OS files for independent re-runs

Refactored from 2 monolithic workflows into 8 targeted ones:

Coordinators (version bump + tag + release creation):
- release.yml: bumps app version, tags v*, creates Gitea release
- sidecar-release.yml: bumps sidecar version, tags sidecar-v*

Per-OS app builds (triggered by v* tags or workflow_dispatch):
- build-app-linux.yml: .deb, .rpm, .AppImage
- build-app-windows.yml: .msi, -setup.exe
- build-app-macos.yml: .dmg

Per-OS sidecar builds (triggered by sidecar-v* tags or workflow_dispatch):
- build-sidecar-linux.yml: CUDA + CPU variants
- build-sidecar-windows.yml: CUDA + CPU variants
- build-sidecar-macos.yml: CPU only

Each build workflow can be re-triggered independently without
re-running the version bump or rebuilding other platforms.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.gitea/workflows/sidecar-release.yml

@@ -0,0 +1,109 @@
+name: Sidecar Release
+
+on:
+  push:
+    branches: [main]
+    paths:
+      - 'client/**'
+      - 'server/**'
+      - 'backend/**'
+      - 'pyproject.toml'
+      - 'local-transcription-headless.spec'
+  workflow_dispatch:
+
+jobs:
+  bump-sidecar-version:
+    name: Bump sidecar version and tag
+    if: "!contains(github.event.head_commit.message, '[skip ci]')"
+    runs-on: ubuntu-latest
+    outputs:
+      version: ${{ steps.bump.outputs.version }}
+      tag: ${{ steps.bump.outputs.tag }}
+      has_changes: ${{ steps.check_changes.outputs.has_changes }}
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 2
+
+      - name: Check for backend changes
+        id: check_changes
+        run: |
+          # If triggered by workflow_dispatch, always build
+          if [ "${{ github.event_name }}" = "workflow_dispatch" ]; then
+            echo "has_changes=true" >> $GITHUB_OUTPUT
+            exit 0
+          fi
+          # Check if relevant files changed in this commit
+          CHANGED=$(git diff --name-only HEAD~1 HEAD -- client/ server/ backend/ pyproject.toml local-transcription-headless.spec 2>/dev/null || echo "")
+          if [ -n "$CHANGED" ]; then
+            echo "has_changes=true" >> $GITHUB_OUTPUT
+            echo "Backend changes detected: $CHANGED"
+          else
+            echo "has_changes=false" >> $GITHUB_OUTPUT
+            echo "No backend changes detected, skipping sidecar build"
+          fi
+
+      - name: Configure git
+        if: steps.check_changes.outputs.has_changes == 'true'
+        run: |
+          git config user.name "Gitea Actions"
+          git config user.email "actions@gitea.local"
+
+      - name: Bump sidecar patch version
+        if: steps.check_changes.outputs.has_changes == 'true'
+        id: bump
+        run: |
+          # Read current version from pyproject.toml
+          CURRENT=$(grep '^version = ' pyproject.toml | head -1 | sed 's/version = "\(.*\)"/\1/')
+          echo "Current sidecar version: ${CURRENT}"
+
+          # Increment patch number
+          MAJOR=$(echo "${CURRENT}" | cut -d. -f1)
+          MINOR=$(echo "${CURRENT}" | cut -d. -f2)
+          PATCH=$(echo "${CURRENT}" | cut -d. -f3)
+          NEW_PATCH=$((PATCH + 1))
+          NEW_VERSION="${MAJOR}.${MINOR}.${NEW_PATCH}"
+          echo "New sidecar version: ${NEW_VERSION}"
+
+          # Update pyproject.toml
+          sed -i "s/^version = \"${CURRENT}\"/version = \"${NEW_VERSION}\"/" pyproject.toml
+
+          # Update version.py
+          sed -i "s/__version__ = \"${CURRENT}\"/__version__ = \"${NEW_VERSION}\"/" version.py
+          sed -i "s/__version_info__ = .*/__version_info__ = (${MAJOR}, ${MINOR}, ${NEW_PATCH})/" version.py
+
+          echo "version=${NEW_VERSION}" >> $GITHUB_OUTPUT
+          echo "tag=sidecar-v${NEW_VERSION}" >> $GITHUB_OUTPUT
+
+      - name: Commit and tag
+        if: steps.check_changes.outputs.has_changes == 'true'
+        env:
+          BUILD_TOKEN: ${{ secrets.BUILD_TOKEN }}
+        run: |
+          NEW_VERSION="${{ steps.bump.outputs.version }}"
+          TAG="${{ steps.bump.outputs.tag }}"
+          git add pyproject.toml version.py
+          git commit -m "chore: bump sidecar version to ${NEW_VERSION} [skip ci]"
+          git tag "${TAG}"
+
+          REMOTE_URL=$(git remote get-url origin | sed "s|://|://gitea-actions:${BUILD_TOKEN}@|")
+          git pull --rebase "${REMOTE_URL}" main || true
+          git push "${REMOTE_URL}" HEAD:main
+          git push "${REMOTE_URL}" "${TAG}"
+
+      - name: Create Gitea release
+        if: steps.check_changes.outputs.has_changes == 'true'
+        env:
+          BUILD_TOKEN: ${{ secrets.BUILD_TOKEN }}
+        run: |
+          REPO_API="${GITHUB_SERVER_URL}/api/v1/repos/${GITHUB_REPOSITORY}"
+          TAG="${{ steps.bump.outputs.tag }}"
+          VERSION="${{ steps.bump.outputs.version }}"
+          RELEASE_NAME="Sidecar v${VERSION}"
+
+          curl -s -X POST \
+            -H "Authorization: token ${BUILD_TOKEN}" \
+            -H "Content-Type: application/json" \
+            -d "{\"tag_name\": \"${TAG}\", \"name\": \"${RELEASE_NAME}\", \"body\": \"Automated sidecar build.\", \"draft\": false, \"prerelease\": false}" \
+            "${REPO_API}/releases"
+          echo "Created release: ${RELEASE_NAME}"