collect: expose interval, host, port, log-dir as optional CLI overrides

-i/--interval, --host, --port, --log-dir can now be passed on the
command line; each overrides the corresponding credentials file value
when given. Defaults remain unchanged (300 s, 0.0.0.0, 9999, ./logs).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

collect.py

@@ -192,6 +192,30 @@ def main() -> None:
         metavar="N",
         help="Keep only the last N records per file (default: unlimited)",
     )
+    p.add_argument(
+        "-i", "--interval",
+        type=int,
+        default=None,
+        metavar="SECONDS",
+        help="Collection interval in seconds (overrides credentials file, default: 300)",
+    )
+    p.add_argument(
+        "--host",
+        default=None,
+        help="Push server bind address (overrides credentials file, default: 0.0.0.0)",
+    )
+    p.add_argument(
+        "--port",
+        type=int,
+        default=None,
+        help="Push server TCP port (overrides credentials file, default: 9999)",
+    )
+    p.add_argument(
+        "--log-dir",
+        default=None,
+        metavar="DIR",
+        help="Directory for rotating log files (overrides credentials file, default: ./logs)",
+    )
     p.add_argument("-v", "--verbose", action="store_true", help="Enable debug logging")
     p.add_argument(
         "--diff",
@@ -241,9 +265,13 @@ def main() -> None:
         else:
             args.domains = raw_domains or "charging,measurements,readiness"
 
+    if args.interval is None:
         args.interval = int(creds_data.get("interval_s", 300))
+    if args.host is None:
         args.host = creds_data.get("host", "0.0.0.0")
+    if args.port is None:
         args.port = int(creds_data.get("port", 9999))
+    if args.log_dir is None:
         args.log_dir = creds_data.get("log_dir", "./logs")
 
     if not args.dry and (not args.username or not args.password):