OpenClaw plugin not working with OpenClaw v2026.5.7

Issue

The OpenClaw plugin from openclaw/ directory does not intercept exec tool calls in OpenClaw v2026.5.7. The before_tool_call hook never fires.

Setup

• RTK CLI v0.39.0 (brew install)
• OpenClaw v2026.5.7 (macOS arm64)
• Plugin installed manually (copied files to global node_modules)

What works

• rtk git status manually: 687 chars vs 1540 chars (55% savings)
• Plugin shows "enabled" in openclaw plugins list

What doesn't

• before_tool_call hook never intercepts exec commands
• openclaw plugins install ./openclaw fails: "package.json missing openclaw.extensions"

The plugin (PR #358, March 2026) uses api.on("before_tool_call", ...) but current OpenClaw appears to have changed its plugin/hook API. Would appreciate guidance on correct API for v2026.5.7.