Add jest test suite, extract pure utils module, fix cron-parser v5 API

- Extract validateWebhookUrl, applyParams, evalCondition, calculateNextRun
  to lib/utils.js so they can be tested without DB connection
- Fix cron-parser v5 API: parseExpression → CronExpressionParser.parse
- Add 31 jest tests covering all four utility functions
- Add test.yml CI workflow running jest on every push/PR
- Add jest devDependency

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

.gitea/workflows/test.yml

@@ -0,0 +1,20 @@
+name: Test
+
+on:
+  push:
+    branches: ["**"]
+  pull_request:
+    branches: ["**"]
+
+jobs:
+  jest:
+    name: JS Tests (jest)
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Install dependencies
+        run: npm install
+
+      - name: Run jest
+        run: npm test