Browser session recovery, price tracking, and dashboard improvements

- Add browser session validation and auto-restart for BestBuy/GameStop scrapers
- Add price change detection and notifications
- Remove PokemonCenter scraper (now uses Chrome Extension)
- Dashboard UI improvements

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

scrapers/gamestop.py

@@ -107,15 +107,55 @@ class GameStopScraper(BaseScraper):
 
     def __init__(self):
         self._stealth_browser = None
+        self._restart_attempts = 0
+        self._max_restart_attempts = 3
 
     def _get_stealth_browser(self):
-        """Get or create stealth browser for GameStop"""
+        """Get or create stealth browser for GameStop, with auto-restart on session errors"""
+        from tools.stealth_browser import StealthBrowser
+
+        # Check if we need to create a new browser
         if self._stealth_browser is None:
-            from tools.stealth_browser import StealthBrowser
+            logger.info("Creating new GameStop stealth browser...")
             self._stealth_browser = StealthBrowser(headless=False, session_name="gamestop")
             self._stealth_browser.start()
+            self._restart_attempts = 0
+            return self._stealth_browser
+
+        # Check if existing session is still valid
+        if not self._stealth_browser.is_session_valid():
+            if self._restart_attempts >= self._max_restart_attempts:
+                logger.error(f"GameStop browser failed after {self._max_restart_attempts} restart attempts")
+                # Reset counter and try one more time after clearing
+                self._restart_attempts = 0
+                self._stealth_browser = None
+                return self._get_stealth_browser()
+
+            logger.warning("GameStop browser session invalid, restarting...")
+            self._restart_attempts += 1
+            self._stealth_browser.restart()
+
         return self._stealth_browser
 
+    def _handle_session_error(self, error: Exception) -> bool:
+        """
+        Check if error is a session error and handle it.
+        Returns True if browser was restarted and operation should be retried.
+        """
+        error_msg = str(error).lower()
+        session_errors = ["invalid session id", "session deleted", "no such session", "browser has closed"]
+
+        if any(err in error_msg for err in session_errors):
+            logger.warning(f"Session error detected: {error}")
+            if self._stealth_browser and self._restart_attempts < self._max_restart_attempts:
+                self._restart_attempts += 1
+                try:
+                    self._stealth_browser.restart()
+                    return True  # Retry operation
+                except Exception as e:
+                    logger.error(f"Failed to restart browser: {e}")
+        return False
+
     def scrape_category_page(self, url: str, max_pages: int = 1) -> List[Product]:
         """
         Scrape a GameStop search/category page for all products
@@ -145,14 +185,33 @@ class GameStopScraper(BaseScraper):
         for page_num in range(1, max_pages + 1):
             products = []
             page_url = url if page_num == 1 else f"{url}&start={24 * (page_num - 1)}"
+            retry_count = 0
+            max_retries = 2
+
+            while retry_count <= max_retries:
+                try:
+                    logger.info(f"Navigating to: {page_url}")
+                    browser.driver.get(page_url)
+                    time.sleep(5)  # Wait for page load
+
+                    html = browser.driver.page_source
+                    break  # Success, exit retry loop
+
+                except Exception as e:
+                    if self._handle_session_error(e) and retry_count < max_retries:
+                        retry_count += 1
+                        logger.info(f"Retrying after browser restart (attempt {retry_count}/{max_retries})")
+                        browser = self._get_stealth_browser()  # Get restarted browser
+                        continue
+                    else:
+                        logger.error(f"Error navigating to {page_url}: {e}")
+                        return all_products
+            else:
+                # while loop completed without break (all retries exhausted)
+                logger.error(f"Failed to load page after {max_retries} retries")
+                return all_products
 
             try:
-                logger.info(f"Navigating to: {page_url}")
-                browser.driver.get(page_url)
-                time.sleep(5)  # Wait for page load
-
-                html = browser.driver.page_source
-
                 # Check for Cloudflare challenge
                 html_lower = html.lower()
                 title = browser.driver.title.lower()