feat: Execute zone - Playwright PC Web + Appium mobile + AI screenshot diff + test conclusion reports

- Add 3 new agents: web-executor, mobile-executor, result-reporter
- web-executor: Playwright multi-browser (Chromium/Firefox/WebKit) automated scripts
- mobile-executor: Appium dual-platform (Android/iOS) automated scripts
- result-reporter: pixel-level AI visual comparison + test conclusion report with screenshots
- Auto-generate executable Python test scripts from Markdown test cases
- Screenshot strategies: on-failure (default) + on-step (optional)
- Visual diff grading: <1% pass / 1-5% minor / 5-15% UI_DIFF / >15% blocker
- Failure multi-classification: REAL_BUG/UI_DIFF/ENV_ISSUE/DATA_ISSUE/CASE_BUG/SCRIPT_ERROR
- requirements.txt: add playwright + Pillow
- Fleet now: 17 agents across 6 battle zones

fleet_config.yml

@@ -6,8 +6,8 @@
 
 fleet:
   name: "Agentic QE Fleet"
-  version: "2.0.0"
-  description: "14 个专业 AI Agent 组成的自治质量工程舰队"
+  version: "2.1.0"
+  description: "17 个专业 AI Agent 组成的自治质量工程舰队（含自动化测试执行）"
 
 # ---------------------------------------------------------------------------
 # 战区配置
@@ -32,6 +32,17 @@ battle_zones:
     auto_confirm: false
     description: "测试策略 + 测试点 + 用例 + 测试数据"
 
+  execute:
+    enabled: true
+    auto_confirm: false
+    description: "PC Web (Playwright) + 移动端 (Appium) 自动化测试执行 + 截图报告"
+    browsers: ["chromium", "firefox", "webkit"]
+    mobile_platforms: ["android", "ios"]
+    screenshot_on_failure: true
+    screenshot_on_step: false
+    timeout_seconds: 120
+    retry_on_failure: 1
+
   review:
     enabled: true
     auto_confirm: false