fix: scroll-fighting, 401 errors, session timeout 90->3600s

- scrollToTop() now respects user scroll position (100px threshold)
- resetScrollLock() called on new messages
- SESSION_TIMEOUT_SECONDS 90 -> 3600 (1 hour) to prevent mid-use expiry
- wrap 10 unprotected authFetch calls in try/catch to kill unhandled rejections

config.py

@@ -35,7 +35,7 @@ def get_amqp_url() -> str:
     return f"amqp://caic:{pw}@localhost:5672/caic"
 
 # --- Auth ---
-SESSION_TIMEOUT_SECONDS = 90
+SESSION_TIMEOUT_SECONDS = 3600
 MAX_PIN_ATTEMPTS = 5
 PIN_LOCKOUT_SECONDS = 300
 ALLOW_DEFAULT_PIN = os.getenv("CAIC_ALLOW_DEFAULT_PIN", "false").lower() == "true"