chore(plugins): add [integrity] SHA-256 hashes for all hook scripts

The daemon's `manifest_missing_integrity_hooks` check (#3804) hard-fails
any registry install whose plugin.toml declares hooks but lacks an
[integrity] entry for each one. All 11 plugins under plugins/ had the
[hooks] table but were missing [integrity], so `librefang plugin install
<name>` would error after download with "missing [integrity] hashes for
hook script(s): ...".

Compute and pin SHA-256 over each `hooks/*.py` under every plugin dir.
The mempalace-indexer entries were already present and are unchanged
(reordered alphabetically by the regenerator).

Verified each plugin.toml still parses (Python tomllib).

plugins/todo-tracker/plugin.toml

@@ -35,3 +35,7 @@ description = "Detecta tareas y acciones mencionadas en las conversaciones, las
 [i18n.fr]
 name = "Suivi de tâches"
 description = "Détecte les actions et tâches mentionnées dans les conversations, les persiste et les rappelle comme contexte."
+
+[integrity]
+"hooks/after_turn.py" = "5c9b524e0c2880152ddad2fcebb6cbe6fc548e3030871d2805a9a789eed80fdc"
+"hooks/ingest.py" = "1cd6a11c07e94dd34bb335f21c19c353b74016ba67a0ebd9bd4cd7cbf227705f"