feat(TASK-039): wire hooks into bundle installs and reconcile builtin hook dirs

Bundles: RemoteLayout.hooks + scan/is_empty/plan routing into hooks_dir,
a functional --filter hooks arm replacing the inert interim arm,
TopCategory::Hooks provenance rows, and per-file 'bundle defines hook
script' summary lines (visibility only, no approval prompt).

Reconciliation: new builtin_manifest module — a hidden per-directory
.builtin-manifest records the files the builtin installer actually owns
(written this run, previously owned, or pending failed deletions);
deletion is strictly manifest-minus-embed so user-created files in the
same directory are never touched. Wired into install_builtin_agents for
agents/<name>/hooks/ and a greenfield minimal Role::install_builtin_role_hooks
for roles/hooks/.

Hardening: bundles are barred from shipping any path component that
aliases .builtin-manifest (Unicode case fold + trailing dot/space,
directories included); manifest entries reuse the bundle store's
is_safe_component rules; malformed manifests fail safe toward keeping
files; role-side reconcile failures degrade to a warning like the
agent side.

src/config/mod.rs

@@ -1,6 +1,7 @@
 mod agent;
 mod app_config;
 mod app_state;
+pub(crate) mod builtin_manifest;
 mod bundles;
 mod input;
 mod install_remote;
@@ -420,6 +421,7 @@ pub fn install_builtins() -> Result<()> {
     Macro::install_macros(false)?;
     Skill::install_builtin_skills(false)?;
     crate::hooks::install_builtin_hooks(false)?;
+    Role::install_builtin_role_hooks(false)?;
     Ok(())
 }