feat: enforce community source cooldown

tests/test_community_cli.py

@@ -0,0 +1,15 @@
+from pathlib import Path
+
+import pytest
+
+from rf4_research.community_cli import enforce_fetch_interval, mark_fetch
+
+
+def test_fetch_cooldown_is_persistent_per_source(tmp_path: Path) -> None:
+    state_file = tmp_path / "fetch-state.json"
+    mark_fetch("rf4map-point", state_file=state_file, now=1_000)
+
+    with pytest.raises(RuntimeError, match="retry in 1800 seconds"):
+        enforce_fetch_interval("rf4map-point", state_file=state_file, now=1_000)
+    enforce_fetch_interval("rf4posts-spot", state_file=state_file, now=1_000)
+    enforce_fetch_interval("rf4map-point", state_file=state_file, now=2_800)