The Settings → Plugins panel keyed off `loaded.enabled` and the four
agentic visibility hooks, both of which are False/empty for exclusive
plugins (memory.provider, model-provider, etc.). Those plugins were
mislabeled as "Disabled" with "No registered lifecycle hooks" even when
fully functional as the active provider for their category.
Surface `manifest.kind` and a derived `activation` field
("enabled" | "disabled" | "exclusive" | "provider") in /api/plugins.
The card render picks a third badge state ("Active (provider)") and a
dedicated empty-hooks line for those rows. `enabled` is preserved in
the payload so older clients still work; new clients should prefer
`activation`.
Fixes#2659
Mark Baker