feat(extension): browser extension for Chrome/Edge/Firefox + CI + v0.8.0

Adds a WXT-based browser extension that replaces manual JS snippet
injection for AI-driven browser testing. The extension auto-connects
to the Muyue server via WebSocket on every page, using the exact
same protocol as the existing snippet — zero backend changes needed.

- Chrome/Edge (MV3) + Firefox (MV2) from single codebase via WXT
- Content script: auto-connect WS, console capture, URL tracking, RPC
- Background service worker: token management, screenshots, badge
- Popup + side panel with server status, sessions, URL config
- CI workflows: build extension, attach .zip to releases
- Makefile targets: ext, ext-chrome, ext-firefox, ext-zip
- Version bumped to 0.8.0

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

.gitea/workflows/ci-pr.yml

@@ -30,13 +30,21 @@ jobs:
           restore-keys: |
             ${{ runner.os }}-go-
 
-      - name: Cache Node modules
+      - name: Cache Node modules (web)
         uses: actions/cache@v4
         with:
           path: web/node_modules
-          key: ${{ runner.os }}-node-${{ hashFiles('web/package-lock.json') }}
+          key: ${{ runner.os }}-node-web-${{ hashFiles('web/package-lock.json') }}
           restore-keys: |
-            ${{ runner.os }}-node-
+            ${{ runner.os }}-node-web-
+
+      - name: Cache Node modules (extension)
+        uses: actions/cache@v4
+        with:
+          path: extension/node_modules
+          key: ${{ runner.os }}-node-ext-${{ hashFiles('extension/package-lock.json') }}
+          restore-keys: |
+            ${{ runner.os }}-node-ext-
 
       - name: Download dependencies
         run: go mod download
@@ -47,13 +55,20 @@ jobs:
           npm ci
           npm run build
 
+      - name: Build extension
+        run: |
+          cd extension
+          npm ci
+          npm run build
+          npm run build:firefox
+
       - name: Vet
         run: go vet ./...
 
       - name: Test
         run: go test ./... -v -race -timeout 60s
 
-      - name: Build
+      - name: Build binary
         run: |
           go build -o muyue ./cmd/muyue/
           ./muyue version