Vendor Chatwoot Vue 3 frontend into frontend/

Copy the Chatwoot (v4.14.0) frontend runnable subset into frontend/ for
customization:
- app/javascript/ (Vue SPA: dashboard, widget, sdk, portal, superadmin)
- app/views/ (ERB templates for vite-plugin-ruby entrypoint resolution)
- app/helpers/, app/assets/ (Rails view helpers, static assets)
- enterprise/ (Enterprise edition frontend overlay)
- config/vite.json, vite.config.ts, bin/vite (Vite-Rails toolchain)
- package.json, pnpm-lock.yaml, tailwind/postcss/eslint configs
- Gemfile, Gemfile.lock (vite_rails gem for bin/vite binstub)

Excluded Rails backend: controllers, models, services, jobs, mailers,
policies, db, lib, spec, public, node_modules.

Update references to the new frontend location:
- .gitignore: exclude frontend build artifacts (node_modules, tmp, packs),
  keep frontend/bin/ and frontend/vendor/ via negation
- backend/scripts/parity_frontend_smoke.sh: CHATWOOT_DIR default
  reference/chatwoot -> ../frontend
- backend/scripts/parity_frontend_browser_smoke.mjs: same default update
- AGENTS.md: add frontend section with Rails/Vite coupling notes
- README: architecture tree includes frontend/

frontend/.github/workflows/lock.yml

@@ -0,0 +1,29 @@
+# We often have cases where users would comment over stale closed Github Issues.
+# This creates unnecessary noise for the original reporter and makes it harder for triaging.
+# This action locks the closed threads once it is inactive for over a month.
+
+name: 'Lock Threads'
+
+on:
+  schedule:
+    - cron: '0 * * * *'
+  workflow_dispatch:
+
+permissions:
+  issues: write
+  pull-requests: write
+
+concurrency:
+  group: lock
+
+jobs:
+  action:
+    runs-on: ubuntu-latest
+    if: ${{ github.repository == 'chatwoot/chatwoot' }}
+    steps:
+      - uses: dessant/lock-threads@v3
+        with: 
+          issue-inactive-days: '30'
+          issue-lock-reason: 'resolved'
+          pr-inactive-days: '30'
+          pr-lock-reason: 'resolved'