feat: consolidate marketplace skills into kyberforge plugin

Moves create-plugin, marketplace-architect, write-skill, and write-eval
from canonical .agents/skills/ into plugins/kyberforge/skills/, along
with all bundled sub-files, evals, and the plugin-marketplace-architecture
research doc. Bundles templates/plugin/ into create-plugin/assets/plugin-template/
so the skill is self-contained after install-time caching. Removes
templates/plugin/ and docs/research/plugin-marketplace-architecture.md
from the repo root as they are now exclusively in the plugin.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

plugins/kyberforge/skills/create-plugin/assets/plugin-template/README.md

@@ -0,0 +1,42 @@
+# PLUGIN_NAME
+
+PLUGIN_DESCRIPTION
+
+## Install
+
+**Claude Code:**
+
+```bash
+claude plugin marketplace add <owner>/<repo>
+claude plugin install PLUGIN_NAME@<marketplace-name>
+```
+
+**GitHub Copilot CLI:**
+
+```bash
+copilot plugin marketplace add <owner>/<repo>
+copilot plugin install PLUGIN_NAME
+```
+
+**Local (development):**
+
+```bash
+# Claude Code
+claude --plugin-dir ./plugins/PLUGIN_NAME
+
+# GitHub Copilot CLI
+copilot plugin install ./plugins/PLUGIN_NAME
+```
+
+## Contents
+
+| Component | Path | Description |
+|---|---|---|
+| Skills | `skills/` | Slash commands available after install |
+| Agents | `agents/` | Role-based agents (`.md` for Claude, `.agent.md` for Copilot) |
+| Hooks | `hooks/hooks.json` (Claude) / `hooks.json` (Copilot) | Event-triggered automation |
+| MCP servers | `.mcp.json` | Model Context Protocol server definitions |
+
+## Author
+
+AUTHOR_NAME