feat: add openclaw-plugin-dev skill

Plugin development reference and workflows based on real development
experience (Dirigent, ContractorAgent, PrismFacet).

Docs: structure, entry-point, hooks, tools, state, config, debugging
Workflows: create-plugin, add-hook

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

openclaw-plugin-dev/SKILL.md

@@ -0,0 +1,21 @@
+---
+name: openclaw-plugin-dev
+description: OpenClaw plugin development — structure, conventions, hooks, tools, install scripts, and debugging. Use when creating, modifying, or debugging OpenClaw plugins.
+---
+
+> Reference docs provide the full specification. Workflows guide specific tasks.
+
+## Reference
+
+- `{baseDir}/docs/structure.md` — Project layout, directory conventions, file naming
+- `{baseDir}/docs/entry-point.md` — Plugin entry format, globalThis patterns, lifecycle protection
+- `{baseDir}/docs/hooks.md` — Hook registration, dedup patterns, available hooks
+- `{baseDir}/docs/tools.md` — Tool registration interface (inputSchema + execute)
+- `{baseDir}/docs/state.md` — State management rules (globalThis vs module-level)
+- `{baseDir}/docs/config.md` — Config schema, install scripts, sensitive fields
+- `{baseDir}/docs/debugging.md` — Dev loop, log keywords, smoke testing
+
+## Workflows
+
+- `{baseDir}/workflows/create-plugin.md` — When creating a new OpenClaw plugin from scratch.
+- `{baseDir}/workflows/add-hook.md` — When adding a new hook handler to an existing plugin.