Update idle time configuration to improve resource management

- Reduced default values for IDLE_MINUTES from 60 to 30 and IDLE_GRACE_MINUTES from 90 to 45 across configuration files and documentation.
- Updated related documentation to reflect the new default idle time settings, ensuring consistency in user guidance and system behavior.

src/gpu_rent/config.py

@@ -255,8 +255,8 @@ def load_config(*, require_auth: bool = True) -> Config:
         scan_pools=(os.environ.get("SCAN_POOLS") or "ru-6,ru-7").strip(),
         default_spot=_as_bool(os.environ.get("DEFAULT_SPOT"), True),
         keep_floating_ip=_as_bool(os.environ.get("KEEP_FLOATING_IP"), False),
-        idle_minutes=_as_int(os.environ.get("IDLE_MINUTES"), 60),
-        idle_grace_minutes=_as_int(os.environ.get("IDLE_GRACE_MINUTES"), 90),
+        idle_minutes=_as_int(os.environ.get("IDLE_MINUTES"), 30),
+        idle_grace_minutes=_as_int(os.environ.get("IDLE_GRACE_MINUTES"), 45),
         pull_output=_as_bool(os.environ.get("PULL_OUTPUT"), False),
         notify_ready=_as_bool(os.environ.get("NOTIFY_READY"), True),
         # Default on: failed up must not leave a billing GPU running.

src/gpu_rent/remote/idle_killer.py

@@ -242,7 +242,7 @@ def main() -> int:
 
     now = time.time()
     grace_from = float(creds.get("grace_from") or 0)
-    grace_minutes = float(creds.get("grace_minutes") or 90)
+    grace_minutes = float(creds.get("grace_minutes") or 45)
     if now < grace_from + grace_minutes * 60:
         left = int(grace_from + grace_minutes * 60 - now)
         log(f"grace {left}s left")
@@ -269,7 +269,7 @@ def main() -> int:
         log(f"busy: {llm_detail}")
         return 0
 
-    idle_minutes = float(creds.get("idle_minutes") or 60)
+    idle_minutes = float(creds.get("idle_minutes") or 30)
     since = read_ts(IDLE_SINCE)
     if since is None:
         write_ts(IDLE_SINCE, now)