feat(install): require an explicit hook decision at the apply layer

The guided installer asks how ECC hooks should run, but that consent
lived only in the wizard path. Running install-apply directly with a
profile that includes hooks-runtime still materialized the hook runtime
with no disclosure and no decision.

Gate the apply layer instead, so every entry point is covered:

- disclose the six hook capability groups when a plan would materialize
  the hook runtime, and refuse to apply until the caller decides
- --enable-hooks confirms the hook runtime; --no-hooks installs the rest
  of the selection without it and records the reduced module closure in
  install-state
- surface the pending decision as a dry-run warning
- show the same capability disclosure in the guided installer's plan
  preview, so the wizard's hook question states what it is asking about

Plans that never materialize hooks (Kimi, --profile minimal,
--without baseline:hooks) are unaffected and need no flag. Repair and
uninstall operate on already-recorded state and stay unchanged.

The capability taxonomy and the held-materialization behavior come from
Samarjeet Singh Tomar's PR #2634, reworked to fit the single-decision
consent model that shipped with the guided installer in #2649.

Co-Authored-By: Samarjeet Singh Tomar <samar_tomar@hotmail.com>
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

hooks/README.md

@@ -26,11 +26,11 @@ For Claude Code manual installs, do not paste the raw repo `hooks.json` into `~/
 Use the installer instead so hook commands are rewritten against your actual Claude root:
 
 ```bash
-bash ./install.sh --target claude --modules hooks-runtime
+bash ./install.sh --target claude --modules hooks-runtime --enable-hooks
 ```
 
 ```powershell
-pwsh -File .\install.ps1 --target claude --modules hooks-runtime
+pwsh -File .\install.ps1 --target claude --modules hooks-runtime --enable-hooks
 ```
 
 That installs resolved hooks to `~/.claude/hooks/hooks.json`. On Windows, the Claude config root is `%USERPROFILE%\\.claude`.