Ignore harness runtime artifacts (.last-cleanup, plugins/.last_inuse_sweep)

.gitignore

@@ -6,6 +6,7 @@ history.jsonl
 
 # Runtime state and caches
 stats-cache.json
+.last-cleanup
 debug/
 telemetry/
 statsig/
@@ -28,6 +29,7 @@ plugins/install-counts-cache.json
 plugins/known_marketplaces.json
 plugins/installed_plugins.json
 plugins/blocklist.json
+plugins/.last_inuse_sweep
 
 # Session and runtime data
 backups/