[FEATURE]: Feature Request: Ship an official built-in "opencode plugin development" skill

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Describe the enhancement you want to request

Hi team,

I'd like to request an official built-in Agent Skill for developing opencode plugins.

Background

opencode already has a great Plugins docs page (https://opencode.ai/docs/plugins/), but there is no built-in SKILL.md that lets an agent load the plugin development workflow on demand. Many users (including me) end up writing their own local skill to encode the plugin structure, hook events, load order, custom tools, dependency handling, and debugging tips.

Why it helps

Agents would get accurate, up-to-date plugin knowledge without needing to fetch the docs at runtime
Reduces risk of hallucinated plugin APIs / wrong hook names
New users get a self-documenting starting point ("minimal plugin template", event list, custom tools via tool(), etc.)
Consistent with how other projects ship official skills alongside docs
Suggestion

Ship a skill (e.g. opencode-plugin-development) in the official skills distribution, covering:

Plugin locations and load order (global config → project config → global plugins → project plugins)
Minimal plugin template and the export const (not default) requirement for local plugins
Full event/hook list (command, file, session, tool, LSP, permission, TUI, etc.)
Custom tools with tool() and Zod schema
Dependency management (package.json in config dir, bun install)
Debugging and logging via client.app.log()
Common gotchas (delayed client usage until server.connected, error catching in hooks)
If you prefer, I can open a PR with the skill content. Thanks for considering!