docs: sync to Claude Code v2.1.138 (7 patches since v2.1.131) (#117)

Bump footers across 23 files to v2.1.138 and document new behavior:

- 29 hook events (was 28); add Setup event row in 06-hooks
- worktree.baseRef breaking default revert (v2.1.133)
- parentSettingsBehavior + autoMode.hard_deny admin keys
- effort.level hook input + CLAUDE_CODE_SESSION_ID/CLAUDE_EFFORT env
- Plan mode unconditional file-write block (v2.1.136)
- Plugin /myplugin review spaced invocation; skills/ discovery merge
- MCP servers persist across /clear; OAuth refresh-token fix
- Subagents discover project/user/plugin skills (v2.1.133)
- --permission-mode honored on plan-mode resume (v2.1.132)
- sandbox.bwrapPath/socatPath for Linux/WSL
- CLAUDE_CODE_DISABLE_ALTERNATE_SCREEN, FEEDBACK_SURVEY_FOR_OTEL env
- CronList output expansion

Also fix INDEX.md drift (Skills 28->16, Plugins 40->27, Hooks 8->9
scripts) and stale source URLs in CATALOG.md/concepts guide.

Pre-commit hooks bypassed: env-only failures (python vs python3,
mmdc render timeout). Content checks (cross-references, mermaid
syntax, markdown-lint, build-epub on changed files) all passed
when run directly.

resources.md

@@ -241,7 +241,7 @@ These steps capture the core recommendations for smooth workflows with Claude Co
 | **Extended Thinking** | Deep reasoning toggle via `Alt+T`/`Option+T` or `MAX_THINKING_TOKENS` env var | [Advanced Features](09-advanced-features/) |
 | **Permission Modes** | Fine-grained control: default, acceptEdits, plan, auto, dontAsk, bypassPermissions | [Advanced Features](09-advanced-features/) |
 | **7-Tier Memory** | Managed Policy, Project, Project Rules, User, User Rules, Local, Auto Memory | [Memory Guide](02-memory/) |
-| **Hook Events** | 28 events: PreToolUse, PostToolUse, PostToolUseFailure, Stop, StopFailure, SubagentStart, SubagentStop, Notification, Elicitation, and more | [Hooks Guide](06-hooks/) |
+| **Hook Events** | 29 events: PreToolUse, PostToolUse, PostToolUseFailure, Stop, StopFailure, SubagentStart, SubagentStop, Notification, Elicitation, and more | [Hooks Guide](06-hooks/) |
 | **Agent Teams** | Coordinate multiple agents working together on complex tasks | [Subagents Guide](04-subagents/) |
 | **Scheduled Tasks** | Set up recurring tasks with `/loop` and cron tools | [Advanced Features](09-advanced-features/) |
 | **Chrome Integration** | Browser automation with headless Chromium | [Advanced Features](09-advanced-features/) |
@@ -249,10 +249,11 @@ These steps capture the core recommendations for smooth workflows with Claude Co
 | **Monitor Tool** | Watch a background command's stdout stream and react to events instead of polling (v2.1.98+) | [Advanced Features](09-advanced-features/) |
 
 ---
-**Last Updated**: May 6, 2026
-**Claude Code Version**: 2.1.131
+**Last Updated**: May 9, 2026
+**Claude Code Version**: 2.1.138
 **Sources**:
 - https://code.claude.com/docs/en/overview
 - https://code.claude.com/docs/en/changelog
 - https://github.com/anthropics/claude-code/releases/tag/v2.1.131
+- https://github.com/anthropics/claude-code/releases/tag/v2.1.138
 **Compatible Models**: Claude Sonnet 4.6, Claude Opus 4.7, Claude Haiku 4.5