ci(gitea): shared composite actions + pipeline generator for Gitea Actions

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AqpXh3hQMMaC74pTjFq4it

Gitea 1.25 cannot run reusable workflows (workflow_call), so the logic of
deploy-app.yml, smoke.yml and ci.yml moves into composite actions under
.gitea/actions/, and each repo gets a thin pipeline rendered by
tools/gitea-pipeline/render.py from repos.json. .github/workflows is left
untouched (Gitea ignores it once .gitea/workflows exists).

.gitea/actions/ci-lint-js/action.yml

@@ -0,0 +1,33 @@
+name: CI - JS lint
+description: >-
+  npm run lint if the repo declares it, else node --check on every *.js
+  (Gitea port of lint-js). Node 22: the GitHub job used Node 20, which is
+  end-of-life.
+runs:
+  using: composite
+  steps:
+    - name: Setup Node
+      uses: actions/setup-node@v4
+      with:
+        node-version: '22'
+        cache: npm
+
+    - name: Install npm dependencies
+      shell: bash
+      run: npm ci
+
+    - name: Lint JavaScript
+      shell: bash
+      run: |
+        if node -e "process.exit(require('./package.json').scripts?.lint ? 0 : 1)" 2>/dev/null; then
+          echo "npm run lint script found - running it."
+          npm run lint
+        else
+          echo "No 'lint' npm script - running node --check syntax scan."
+          find . -name '*.js' \
+            -not -path './vendor/*' \
+            -not -path './node_modules/*' \
+            -not -path './.git/*' \
+            -not -path './.peptide-e2e/*' \
+            -print0 | xargs -0 -r -I{} node --check {}
+        fi