start_monitoring assigned self.observer before checking that any directory
existed, so with no valid directory the monitor was stuck "already running"
and stop_monitoring raised on join of a never-started observer. Directories
are validated first and only a started observer is kept; stop_monitoring is
safe to call at any time and always joins. New is_monitoring property.
The per-image threading.Timer is replaced by one daemon worker: paths are
deduplicated and bounded (MAX_PENDING_IMAGES), processed in creation order
(batch images pop the prompt queue in order) after the processing delay and
once the file size is unchanged across two reads.
* fix: diagnostics, backup, and restore now respect config.json db path (#132)
* test: add regression tests for config-aware diagnostics and backup (#132)
* fix(test): use fresh event loop to avoid aiohttp test pollution
* fix: don't kill singleton image monitor when node instance is garbage collected
The __del__ method was calling stop_monitoring() on the shared singleton
ImageMonitor, killing it for ALL nodes whenever any single node instance
was garbage collected between workflow runs. This caused the monitor to
restart on every execution and miss image save events due to race conditions.
* test: add regression tests for image monitor singleton lifecycle
Ensures cleanup/del never stops the shared monitor, singleton is
thread-safe, and observer survives across node instance lifecycles.
* style: address PR review — log suppressed exceptions, remove unused imports
Vito Sansevero