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/app/javascript/dashboard/api/specs/inboxes.spec.js

@@ -0,0 +1,52 @@
+import inboxesAPI from '../inboxes';
+import ApiClient from '../ApiClient';
+
+describe('#InboxesAPI', () => {
+  it('creates correct instance', () => {
+    expect(inboxesAPI).toBeInstanceOf(ApiClient);
+    expect(inboxesAPI).toHaveProperty('get');
+    expect(inboxesAPI).toHaveProperty('show');
+    expect(inboxesAPI).toHaveProperty('create');
+    expect(inboxesAPI).toHaveProperty('update');
+    expect(inboxesAPI).toHaveProperty('delete');
+    expect(inboxesAPI).toHaveProperty('getCampaigns');
+    expect(inboxesAPI).toHaveProperty('getAgentBot');
+    expect(inboxesAPI).toHaveProperty('setAgentBot');
+    expect(inboxesAPI).toHaveProperty('syncTemplates');
+  });
+
+  describe('API calls', () => {
+    const originalAxios = window.axios;
+    const axiosMock = {
+      post: vi.fn(() => Promise.resolve()),
+      get: vi.fn(() => Promise.resolve()),
+      patch: vi.fn(() => Promise.resolve()),
+      delete: vi.fn(() => Promise.resolve()),
+    };
+
+    beforeEach(() => {
+      window.axios = axiosMock;
+    });
+
+    afterEach(() => {
+      window.axios = originalAxios;
+    });
+
+    it('#getCampaigns', () => {
+      inboxesAPI.getCampaigns(2);
+      expect(axiosMock.get).toHaveBeenCalledWith('/api/v1/inboxes/2/campaigns');
+    });
+
+    it('#deleteInboxAvatar', () => {
+      inboxesAPI.deleteInboxAvatar(2);
+      expect(axiosMock.delete).toHaveBeenCalledWith('/api/v1/inboxes/2/avatar');
+    });
+
+    it('#syncTemplates', () => {
+      inboxesAPI.syncTemplates(2);
+      expect(axiosMock.post).toHaveBeenCalledWith(
+        '/api/v1/inboxes/2/sync_templates'
+      );
+    });
+  });
+});