feat(02-01): create SKILL.md with valid frontmatter

- YAML frontmatter with name: gsd-openclaw
- Description contains /gsd:* trigger patterns
- Documents all supported GSD commands
- Explains project context switching

Requirements: OCLW-01, OCLW-02

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

gsd-openclaw/skill/SKILL.md

@@ -0,0 +1,45 @@
+---
+name: gsd-openclaw
+description: GSD project management via /gsd:* commands. Triggers on /gsd:new-project, /gsd:plan, /gsd:status, /gsd:use and other GSD slash commands.
+---
+
+# GSD-OpenClaw Skill
+
+This skill enables GSD (Get Shit Done) project management through chat interfaces via OpenClaw.
+
+## When to Use
+
+This skill triggers when users send messages starting with `/gsd:` in any channel where OpenClaw is configured. Use this skill to:
+
+- Create and manage GSD projects
+- Switch between project contexts
+- Check project status
+- Execute planning and shipping workflows
+
+## Commands
+
+| Command | Description |
+|---------|-------------|
+| `/gsd:new-project <name>` | Create a new GSD project |
+| `/gsd:use <project>` | Switch to a project context |
+| `/gsd:status` | Show current project status |
+| `/gsd:plan` | Run planning phase |
+| `/gsd:ship` | Ship the current phase |
+| `/gsd:help` | Show available commands |
+
+## Project Context
+
+GSD manages multiple projects, each with its own workspace and state. Use `/gsd:use <project>` to switch the active project context before running other commands.
+
+Example:
+```
+/gsd:new-project my-auth-service
+/gsd:use my-auth-service
+/gsd:status
+```
+
+## Integration Notes
+
+- Sessions persist in tmux for long-running operations
+- State is checkpointed to JSON for recovery
+- Multiple projects can run concurrently without interference