feat(extension): Chrome/Edge only + side panel chat tabs (v0.9.0)

- Remove Firefox build support (CI, Makefile, wxt config)
- Fix chrome.alarms undefined error (add 'alarms' permission)
- Add Chat tab to side panel connected to Studio API (/api/chat)
- Streaming SSE, tool calls, code blocks, thinking display
- Shared chat history with desktop Studio
- New lib/api.js client for extension chat endpoints

💘 Generated with Crush

Assisted-by: GLM-5.1 via Crush <crush@charm.land>

extension/wxt.config.js

@@ -2,19 +2,17 @@ import { defineConfig } from 'wxt';
 
 export default defineConfig({
   srcDir: 'src',
-  suppressWarnings: {
-    firefoxDataCollection: true,
-  },
-  manifest: ({ browser }) => ({
+  manifest: {
     name: 'Muyue',
     description: 'AI-powered browser testing & automation — connected to your Muyue desktop app',
     permissions: [
       'storage',
       'activeTab',
       'tabs',
-      ...(browser === 'chrome' ? ['sidePanel'] : []),
+      'sidePanel',
       'scripting',
       'notifications',
+      'alarms',
     ],
     host_permissions: ['http://127.0.0.1:*/*', 'http://localhost:*/*'],
     action: {
@@ -26,5 +24,5 @@ export default defineConfig({
     side_panel: {
       default_path: 'sidepanel.html',
     },
-  }),
+  },
 });