ci: optimize workflows to cut redundant runs (#465)

* ci: optimize workflows to cut redundant runs and add timeout protection

Skip validation jobs (build, test, lint, Docker, E2E) on push-to-main
since code was already validated on the PR. Skip CI entirely for
release-please PRs (version bump only). Add timeout-minutes to all jobs
to prevent hung runners from burning 360 min (GitHub default). Add npm
caching to the start-app composite action. Add concurrency control to
docker-publish. Group Dependabot updates to batch PRs per ecosystem.

Estimated savings: ~10 min per release cycle, ~30-40 min/day.

* chore: add tsbuildinfo to gitignore

.github/workflows/ci.yml

@@ -18,12 +18,16 @@ concurrency:
   cancel-in-progress: true
 
 # ---------------------------------------------------------------------------
-# Build & Validation (runs on PRs and push to main)
+# Build & Validation (PRs only, skipped for release-please PRs)
 # ---------------------------------------------------------------------------
 jobs:
   backend:
     name: Backend (Build, Test, Lint)
     runs-on: ubuntu-latest
+    timeout-minutes: 10
+    if: >-
+      github.event_name == 'pull_request'
+      && github.head_ref != 'release-please--branches--main--components--sencho'
     steps:
       - name: Checkout Code
         uses: actions/checkout@v6
@@ -58,6 +62,10 @@ jobs:
   frontend:
     name: Frontend (Build, Lint)
     runs-on: ubuntu-latest
+    timeout-minutes: 10
+    if: >-
+      github.event_name == 'pull_request'
+      && github.head_ref != 'release-please--branches--main--components--sencho'
     steps:
       - name: Checkout Code
         uses: actions/checkout@v6
@@ -88,6 +96,10 @@ jobs:
   docker-validate:
     name: Docker Build & Scan
     runs-on: ubuntu-latest
+    timeout-minutes: 15
+    if: >-
+      github.event_name == 'pull_request'
+      && github.head_ref != 'release-please--branches--main--components--sencho'
     steps:
       - name: Checkout Code
         uses: actions/checkout@v6
@@ -117,12 +129,16 @@ jobs:
         continue-on-error: true
 
   # ---------------------------------------------------------------------------
-  # E2E Tests (runs on PRs and push to main)
+  # E2E Tests (PRs only, skipped for release-please PRs)
   # ---------------------------------------------------------------------------
   e2e:
     name: E2E Tests (Playwright)
     runs-on: ubuntu-latest
+    timeout-minutes: 15
     needs: [backend, frontend]
+    if: >-
+      github.event_name == 'pull_request'
+      && github.head_ref != 'release-please--branches--main--components--sencho'
     steps:
       - name: Checkout Code
         uses: actions/checkout@v6
@@ -154,11 +170,11 @@ jobs:
   update-screenshots:
     name: Refresh Doc Screenshots
     runs-on: ubuntu-latest
+    timeout-minutes: 15
     if: >-
       github.event_name == 'push'
       && github.ref == 'refs/heads/main'
       && startsWith(github.event.head_commit.message, 'chore(main): release')
-    needs: [backend, frontend]
     permissions:
       contents: write
       pull-requests: write
@@ -201,6 +217,7 @@ jobs:
   sync-docs:
     name: Sync Docs to sencho-docs
     runs-on: ubuntu-latest
+    timeout-minutes: 5
     if: github.event_name == 'push' && github.ref == 'refs/heads/main'
     steps:
       - name: Checkout Sencho repo

.github/workflows/docker-publish.yml

@@ -6,10 +6,15 @@ on:
       - 'v*'
   workflow_dispatch:
 
+concurrency:
+  group: docker-publish
+  cancel-in-progress: true
+
 jobs:
   push_to_registry:
     name: Push Docker image to Docker Hub
     runs-on: ubuntu-latest
+    timeout-minutes: 30
     steps:
       - name: Check out the repo
         uses: actions/checkout@v6