docs: sync to Claude Code v2.1.131 (3 patches since v2.1.126)

Sync covers v2.1.128, v2.1.129, and v2.1.131 (May 2026). Highlights:
gateway /v1/models discovery is now opt-in (CLAUDE_CODE_ENABLE_GATEWAY_MODEL_DISCOVERY),
added --plugin-url flag, disableRemoteControl setting, /mcp tool-count display,
expanded skillOverrides values, /context viz no longer leaks into conversation,
Ctrl+R cross-project default. Also reconciles slash-command count to 60+ and
fixes the skill-count entry in CATALOG.

resources.md

@@ -249,10 +249,10 @@ 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 2, 2026
-**Claude Code Version**: 2.1.126
+**Last Updated**: May 6, 2026
+**Claude Code Version**: 2.1.131
 **Sources**:
 - https://code.claude.com/docs/en/overview
 - https://code.claude.com/docs/en/changelog
-- https://github.com/anthropics/claude-code/releases/tag/v2.1.126
+- https://github.com/anthropics/claude-code/releases/tag/v2.1.131
 **Compatible Models**: Claude Sonnet 4.6, Claude Opus 4.7, Claude Haiku 4.5