fix: refill from expanded candidate history

main.py

@@ -52,8 +52,6 @@ def _worker_command() -> list[str]:
         os.getenv("MODELHUB_AGENT_IDLE_INTERVAL_SECONDS", "60"),
         "--post-cycle-cooldown-seconds",
         os.getenv("MODELHUB_AGENT_POST_CYCLE_COOLDOWN_SECONDS", "2"),
-        "--max-submits-per-run",
-        os.getenv("MODELHUB_AGENT_MAX_SUBMITS_PER_RUN", "0"),
         "--skip-history-archive",
     ]
 
@@ -70,6 +68,9 @@ def _worker_command() -> list[str]:
         cmd.extend(["--gpus", gpus])
 
     cmd.extend(_csv_args("MODELHUB_AGENT_EXTRA_ARGS"))
+    # The hosted agent's goal is to fill every currently available slot. Keep
+    # this last so an old environment or extra-args value cannot restore "5".
+    cmd.extend(["--max-submits-per-run", "0"])
     return cmd