fix(plugins): stop core updates from resurrecting uninstalled built-in plugins (#368)

* fix(plugins): stop core updates from resurrecting uninstalled built-in plugins

Built-in plugins (e.g. web-ui-info, starlark-apps) are committed into the
repo under plugin-repos/. When a user uninstalls one, a subsequent core
`git pull` update restores the committed files, so the plugin reappears on
every update. The update endpoint stashes the deletion and never pops it,
and `git pull` faithfully restores any committed file whose deletion was
never committed — so excluding plugin-repos/ from the stash can't fix this
(it would only make `git pull --rebase` fail on a dirty tree).

Add a persistent uninstall registry (config/uninstalled_plugins.json,
gitignored) that survives restarts, unlike the existing in-memory tombstone:

- Uninstall records the plugin id; install clears it.
- purge_uninstalled_plugins() re-removes any recorded plugin whose directory
  reappears on disk; called after a successful git-pull update and at web
  startup (covers manual `git pull` on the Pi too).
- The state reconciler also refuses to auto-repair a persistently
  uninstalled plugin.

Wires up mark_recently_uninstalled in the uninstall flow (previously only
referenced by tests) via the new persistent record.

Adds regression tests covering record/forget/purge lifecycle, persistence
across manager instances, and corrupt-registry tolerance.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* fix(plugins): validate uninstall-registry ids and lock registry writes

Address review feedback on the persistent uninstall registry:

- Critical: validate plugin ids on read/record and add a containment guard
  in purge_uninstalled_plugins. A corrupt or hand-edited registry entry of
  "" resolves to the plugins root, so purge could have deleted every plugin;
  traversal ids ("..", "../x") could target paths outside the root. Invalid
  ids are now dropped on read, refused on record, and never removed unless
  the path is a direct child of the plugins directory.
- Major: guard record/forget read-modify-write with a lock so concurrent
  install/uninstall requests can't lose updates.
- Minor: narrow the startup and post-update purge exception handlers from
  bare Exception to (OSError, RuntimeError).

Adds regression tests for empty-id, traversal-id, and invalid-record cases.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

web_interface/blueprints/api_v3.py

@@ -1559,6 +1559,20 @@ def execute_system_action():
                     pull_message = f"Code updated successfully. Local changes were automatically stashed.{stash_info}"
                 if result.stdout and "Already up to date" not in result.stdout:
                     pull_message = f"Code updated successfully.{stash_info}"
+                # A `git pull` restores built-in plugins (committed under
+                # plugin-repos/) even if the user uninstalled them. Re-remove
+                # any the user previously uninstalled so the update doesn't
+                # resurrect them.
+                if api_v3.plugin_store_manager:
+                    try:
+                        purged = api_v3.plugin_store_manager.purge_uninstalled_plugins()
+                        if purged:
+                            logger.info(
+                                "Re-removed %d uninstalled plugin(s) restored by update: %s",
+                                len(purged), ", ".join(purged),
+                            )
+                    except (OSError, RuntimeError) as purge_err:
+                        logger.warning("Post-update plugin purge failed: %s", purge_err)
             else:
                 logger.warning("git pull failed (returncode=%d): %s", result.returncode, result.stderr)
                 pull_message = "Update failed; check logs for details"
@@ -2933,6 +2947,13 @@ def _do_transactional_uninstall(plugin_id, preserve_config):
         api_v3.schema_manager.invalidate_cache(plugin_id)
     if api_v3.plugin_state_manager:
         api_v3.plugin_state_manager.remove_plugin_state(plugin_id)
+    # Persistently record the uninstall so a later core `git pull` update
+    # cannot resurrect a built-in plugin (committed under plugin-repos/) that
+    # the user removed. Best-effort: never fail the uninstall over this.
+    try:
+        api_v3.plugin_store_manager.record_uninstalled_plugin(plugin_id)
+    except Exception as record_err:
+        logger.warning("Could not record uninstall for %s: %s", plugin_id, record_err)
     return True, None