fix: retry WebSocket connection on first run instead of silent exit

fetch_targets() called sys.exit(0) on ConnectionRefusedError. Steam's CEF
debugger on port 8080 is not always ready on first run, so the scanner exited
silently and added no shortcuts (issue #895, first-run half).

Replace with retry + exponential backoff (15 attempts, 2s base, 10s cap),
print progress so the retry is visible, and raise the last error instead of
exiting silently.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

NSLGameScanner.py

@@ -1835,23 +1835,53 @@ THEMEMUSIC_CODE = r"""(function () {
 
 
 
-# Utility: Fetch debugger targets
-def fetch_targets(host, port):
+# Utility: Fetch debugger targets with retry
+def fetch_targets(host, port, max_retries=15, base_delay=2):
+    """Fetch debugger targets from Steam CEF debugger, with retry logic.
+
+    Steam's CEF debugger on port 8080 may not be listening on first run.
+    Retries with exponential backoff (capped at 10s) up to max_retries times.
+
+    Old behavior: called sys.exit(0) on any connection failure (silent exit).
+    New behavior: retries up to max_retries times, then raises the last error.
+    """
+    import time
+
+    last_error = None
+    for attempt in range(max_retries):
         try:
             conn = http.client.HTTPConnection(host, port, timeout=5)
             conn.request("GET", "/json")
             resp = conn.getresponse()
 
             if resp.status != 200:
-            print(f"Failed to fetch targets: {resp.status} {resp.reason}")
-            sys.exit(0)
+                msg = f"Failed to fetch targets: {resp.status} {resp.reason}"
+                print(msg)
+                raise Exception(msg)
 
             data = resp.read()
-        return json.loads(data)
+            targets = json.loads(data)
 
-    except (ConnectionRefusedError, socket.timeout, http.client.CannotSendRequest, http.client.RemoteDisconnected, Exception) as e:
-        print(f"Error fetching debugger targets: {e}")
-        sys.exit(0)
+            if attempt > 0:
+                print(f"Connected to Steam debugger on attempt {attempt + 1}/{max_retries}")
+
+            return targets
+
+        except (ConnectionRefusedError, socket.timeout,
+                http.client.CannotSendRequest, http.client.RemoteDisconnected,
+                OSError, Exception) as e:
+            last_error = e
+            if attempt < max_retries - 1:
+                delay = min(base_delay * (attempt + 1), 10)
+                print(f"Steam debugger not ready (attempt {attempt + 1}/{max_retries}), "
+                      f"retrying in {delay}s... ({e})")
+                time.sleep(delay)
+            else:
+                print(f"ERROR: Could not connect to Steam debugger at {host}:{port} "
+                      f"after {max_retries} attempts.")
+                print(f"Make sure Steam is running with these launch options:")
+                print(f"  -dev -cef-enable-debugging -cef-single-process")
+                raise last_error
 
         finally:
             try: