fix: Always save diagnostics on any error

- Add saveDiagnostics method
- Use defer in Generate to catch all errors
- Simplify typeInput error handling
- Automatic screenshot and HTML dump on failure

internal/providers/geminiweb/playwright_provider.go

@@ -114,7 +114,15 @@ func (p *PlaywrightProvider) launchIfNeeded() error {
 }
 
 // Generate 生成回應
-func (p *PlaywrightProvider) Generate(ctx context.Context, model string, messages []apitypes.Message, tools []apitypes.Tool, cb func(apitypes.StreamChunk)) error {
+func (p *PlaywrightProvider) Generate(ctx context.Context, model string, messages []apitypes.Message, tools []apitypes.Tool, cb func(apitypes.StreamChunk)) (err error) {
+	// 確保在返回錯誤時保存診斷
+	defer func() {
+		if err != nil {
+			fmt.Println("[GeminiWeb] Error occurred, saving diagnostics...")
+			_ = p.saveDiagnostics()
+		}
+	}()
+
 	fmt.Printf("[GeminiWeb] Starting generation with model: %s\n", model)
 
 	// 1. 確保瀏覽器已啟動
@@ -237,6 +245,36 @@ func (p *PlaywrightProvider) Close() error {
 	return nil
 }
 
+// saveDiagnostics 保存診斷信息
+func (p *PlaywrightProvider) saveDiagnostics() error {
+	if p.page == nil {
+		return fmt.Errorf("no page available")
+	}
+
+	// 截圖
+	screenshotPath := "/tmp/gemini-debug.png"
+	if _, err := p.page.Screenshot(playwright.PageScreenshotOptions{
+		Path: playwright.String(screenshotPath),
+	}); err == nil {
+		fmt.Printf("[GeminiWeb] Screenshot saved: %s\n", screenshotPath)
+	}
+
+	// HTML
+	htmlPath := "/tmp/gemini-debug.html"
+	if html, err := p.page.Content(); err == nil {
+		if err := os.WriteFile(htmlPath, []byte(html), 0644); err == nil {
+			fmt.Printf("[GeminiWeb] HTML saved: %s\n", htmlPath)
+		}
+	}
+
+	// 輸出頁面信息
+	url := p.page.URL()
+	title, _ := p.page.Title()
+	fmt.Printf("[GeminiWeb] Diagnostics: URL=%s, Title=%s\n", url, title)
+
+	return nil
+}
+
 // waitForPageReady 等待頁面完全就緒（project-golem 策略）
 func (p *PlaywrightProvider) waitForPageReady() error {
 	fmt.Println("[GeminiWeb] Checking for ready state...")
@@ -393,61 +431,10 @@ func (p *PlaywrightProvider) typeInput(text string) error {
 	}
 
 	if !found {
-		// 保存診斷信息
-		screenshotPath := "/tmp/gemini-debug.png"
-		htmlPath := "/tmp/gemini-debug.html"
-
-		// 截圖
-		if _, err := p.page.Screenshot(playwright.PageScreenshotOptions{
-			Path: playwright.String(screenshotPath),
-		}); err == nil {
-			fmt.Printf("[GeminiWeb] Screenshot saved: %s\n", screenshotPath)
-		}
-
-		// HTML
-		if html, err := p.page.Content(); err == nil {
-			if err := os.WriteFile(htmlPath, []byte(html), 0644); err == nil {
-				fmt.Printf("[GeminiWeb] HTML saved: %s\n", htmlPath)
-			}
-		}
-
-		// 輸出調試信息
+		// 錯誤會被 Generate 的 defer 捕獲並保存診斷
 		url := p.page.URL()
 		title, _ := p.page.Title()
-		fmt.Printf("[GeminiWeb] DEBUG: URL=%s\n", url)
-		fmt.Printf("[GeminiWeb] DEBUG: Title=%s\n", title)
-
-		// 嘗試用 JavaScript 找輸入框
-		fmt.Println("[GeminiWeb] Trying JavaScript element search...")
-		_, _ = p.page.Evaluate(`
-			() => {
-				console.log('=== DEBUG: Looking for input elements ===');
-				const selectors = [
-					'.ProseMirror',
-					'rich-textarea',
-					'div[role="textbox"]',
-					'div[contenteditable="true"]',
-					'textarea',
-					'input'
-				];
-				for (const sel of selectors) {
-					const els = document.querySelectorAll(sel);
-					if (els.length > 0) {
-						console.log('Found', els.length, 'elements for:', sel);
-					}
-				}
-				
-				// 檢查頁面中所有可交互元素
-				const interactable = document.querySelectorAll('div[contenteditable="true"], textarea, input[type="text"], [role="textbox"]');
-				console.log('Total interactable elements:', interactable.length);
-				
-				return { found: false };
-			}
-		`)
-
-		// 顯示最後的URL和標題
-		return fmt.Errorf("input field not found (URL=%s, Title=%s). Screenshot saved to %s, HTML saved to %s",
-			url, title, screenshotPath, htmlPath)
+		return fmt.Errorf("input field not found (URL=%s, Title=%s). Diagnostics will be saved to /tmp/", url, title)
 	}
 
 	// Focus 並填充（Playwright 自動等待）