feat: log FB token remaining_days on validation

app.py

@@ -194,18 +194,19 @@ if __name__ == "__main__":
                             logger.exception("Failed to write token validation failure to log.txt")
                         ok = False
                     else:
-                        # determine expiry classification if available
+                        # determine expiry classification if available and log remaining days
                         expires_at = debug_info.get("expires_at")
+                        remaining_days = None
                         if expires_at:
                             try:
                                 expires_at = int(expires_at)
                                 import time as _time
                                 delta = expires_at - int(_time.time())
-                                days = max(0, delta // 86400)
-                                if days >= 30:
-                                    token_type = f"long-lived (~{days} days)"
+                                remaining_days = max(0, delta // 86400)
+                                if remaining_days >= 30:
+                                    token_type = f"long-lived (~{remaining_days} days)"
                                 else:
-                                    token_type = f"short-lived (~{days} days)"
+                                    token_type = f"short-lived (~{remaining_days} days)"
                             except Exception:
                                 token_type = "unknown-expiry"
                         else:
@@ -213,7 +214,11 @@ if __name__ == "__main__":
                         logger.info("Facebook token looks valid (%s)", token_type)
                         try:
                             with open("log.txt", "a", encoding="utf-8") as lf:
-                                lf.write(f"[{__import__('time').strftime('%Y-%m-%d %H:%M:%S')}] FB_TOKEN_VALIDATION_OK type={token_type}\n")
+                                entry = f"[{__import__('time').strftime('%Y-%m-%d %H:%M:%S')}] FB_TOKEN_VALIDATION_OK type={token_type}"
+                                if remaining_days is not None:
+                                    entry += f" remaining_days={remaining_days}"
+                                entry += "\n"
+                                lf.write(entry)
                         except Exception:
                             logger.exception("Failed to write token validation ok to log.txt")
             except Exception as e: