fix: Add proper page ready check before finding input

Key improvements:
- Wait for page to fully load (SPA needs time)
- Wait for input field to be visible before typing
- Check login status only after page is ready
- Add fallback wait (3 seconds) if first attempt fails
- Properly handle error messages

Based on project-golem's PageInteractor.waitForReady()

internal/providers/geminiweb/playwright_provider.go

@@ -132,10 +132,15 @@ func (p *PlaywrightProvider) Generate(ctx context.Context, model string, message
 		}); err != nil {
 			return fmt.Errorf("failed to navigate: %w", err)
 		}
-		time.Sleep(2 * time.Second)
 	}
 
-	// 3. 檢查登入狀態
+	// 3. 等待頁面完全載入（project-golem 策略）
+	fmt.Println("[GeminiWeb] Waiting for page to be ready...")
+	if err := p.waitForPageReady(); err != nil {
+		fmt.Printf("[GeminiWeb] Warning: %v\n", err)
+	}
+
+	// 4. 檢查登入狀態
 	fmt.Println("[GeminiWeb] Checking login status...")
 	loggedIn := p.isLoggedIn()
 	if !loggedIn {
@@ -151,11 +156,6 @@ func (p *PlaywrightProvider) Generate(ctx context.Context, model string, message
 		fmt.Println("[GeminiWeb] Logged in")
 	}
 
-	// 4. 等待頁面就緒
-	if err := p.waitForReady(); err != nil {
-		fmt.Printf("[GeminiWeb] Warning: %v\n", err)
-	}
-
 	// 5. 建構提示詞
 	prompt := buildPromptFromMessagesPlaywright(messages)
 	fmt.Printf("[GeminiWeb] Typing prompt (%d chars)...\n", len(prompt))
@@ -201,6 +201,58 @@ func (p *PlaywrightProvider) Close() error {
 	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...")
+
+	// 1. 等待停止按鈕消失（如果存在）
+	_, _ = p.page.WaitForSelector("button[aria-label*='Stop'], button[aria-label*='停止']", playwright.PageWaitForSelectorOptions{
+		State:   playwright.WaitForSelectorStateDetached,
+		Timeout: playwright.Float(5000),
+	})
+
+	// 2. 等待輸入框出現（關鍵！）
+	inputSelectors := []string{
+		".ProseMirror",
+		"rich-textarea",
+		"div[role='textbox']",
+		"div[contenteditable='true']",
+		"textarea",
+	}
+
+	var lastErr error
+	for _, sel := range inputSelectors {
+		fmt.Printf("  Checking for: %s\n", sel)
+		locator := p.page.Locator(sel)
+		if err := locator.WaitFor(playwright.LocatorWaitForOptions{
+			Timeout: playwright.Float(10000),
+			State:   playwright.WaitForSelectorStateVisible,
+		}); err == nil {
+			fmt.Printf("  ✓ Input field found: %s\n", sel)
+			return nil
+		} else {
+			lastErr = err
+		}
+	}
+
+	// 3. 如果都找不到，給頁面更多時間
+	fmt.Println("[GeminiWeb] Input not found immediately, waiting longer...")
+	time.Sleep(3 * time.Second)
+
+	for _, sel := range inputSelectors {
+		locator := p.page.Locator(sel)
+		if err := locator.WaitFor(playwright.LocatorWaitForOptions{
+			Timeout: playwright.Float(5000),
+			State:   playwright.WaitForSelectorStateVisible,
+		}); err == nil {
+			fmt.Printf("  ✓ Input field found after wait: %s\n", sel)
+			return nil
+		}
+	}
+
+	return fmt.Errorf("input field not ready: %w", lastErr)
+}
+
 // isLoggedIn 檢查是否已登入
 func (p *PlaywrightProvider) isLoggedIn() bool {
 	// 嘗試找輸入框（登入狀態的主要特徵）
@@ -213,29 +265,14 @@ func (p *PlaywrightProvider) isLoggedIn() bool {
 	}
 
 	for _, sel := range selectors {
-		if _, err := p.page.WaitForSelector(sel, playwright.PageWaitForSelectorOptions{
-			Timeout: playwright.Float(3000),
-		}); err == nil {
+		locator := p.page.Locator(sel)
+		if count, _ := locator.Count(); count > 0 {
 			return true
 		}
 	}
 	return false
 }
 
-// waitForReady 等待頁面就緒
-func (p *PlaywrightProvider) waitForReady() error {
-	fmt.Println("[GeminiWeb] Checking if page is ready...")
-
-	// 等待停止按鈕消失（如果存在）
-	_, _ = p.page.WaitForSelector("button[aria-label*='Stop']", playwright.PageWaitForSelectorOptions{
-		State:   playwright.WaitForSelectorStateDetached,
-		Timeout: playwright.Float(5000),
-	})
-
-	fmt.Println("[GeminiWeb] Page is ready")
-	return nil
-}
-
 // typeInput 輸入文字（使用 Playwright 的 Auto-wait）
 func (p *PlaywrightProvider) typeInput(text string) error {
 	fmt.Println("[GeminiWeb] Looking for input field...")