## Why
Installed-plugin inventory fetches could keep following pagination cursors
without an overall bound, delaying release of the plugin mutation gate.
## What changed
- Limit each inventory fetch to 60 seconds and 100 pages, and reject repeated
pagination cursors.
- Request 200 items per page for scoped inventory fetches as well as all-scope
fetches.
- Report overall fetch timeouts as `remote_catalog_timeout`.
## Testing
Add coverage for cursor cycles, completion at the page limit, and overall
timeout cancellation after successful pages. Verify that failed pagination
preserves the cached inventory and plugin files and releases the mutation gate.
GitOrigin-RevId: e8429dd804581041d102defa9d19db02bcb1739b
Matthew Zeng
9b39316997