add github actions ci workflow

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.github/workflows/build.yml

@@ -0,0 +1,30 @@
+name: Build Workflow
+
+on:
+  push:
+    branches: [main]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Run tests
+        run: bash tests/test_tmux_search.sh
+
+      - name: Build .alfredworkflow
+        run: bash build/build_workflow.sh
+
+      - name: Extract version
+        id: version
+        run: |
+          VERSION=$(grep -A1 '<key>version</key>' info.plist | grep '<string>' | sed 's/.*<string>//;s/<\/string>.*//')
+          echo "version=${VERSION}" >> "$GITHUB_OUTPUT"
+
+      - name: Create release
+        uses: softprops/action-gh-release@v2
+        with:
+          tag_name: v${{ steps.version.outputs.version }}
+          name: v${{ steps.version.outputs.version }}
+          files: dist/alfred-tmux-cheat-sheet.alfredworkflow