[2.8.1] Add GitHub/Linear issue creation to /plan command

- Add "Create Issue" option to post-generation menu in /plan
- Detect project tracker from user's CLAUDE.md (project_tracker: github or linear)
- Use gh issue create for GitHub, linear CLI for Linear
- Show issue URL after creation and offer to continue to /work or /plan_review

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

plugins/compounding-engineering/.claude-plugin/plugin.json

@@ -1,6 +1,6 @@
 {
   "name": "compounding-engineering",
-  "version": "2.8.0",
+  "version": "2.8.1",
   "description": "AI-powered development tools. 24 agents, 16 commands, 11 skills, 2 MCP servers for code review, research, design, and workflow automation.",
   "author": {
     "name": "Kieran Klaassen",