Initial commit: pi-project-map skill scaffolding

- Design doc with full spec (dense markdown format, hybrid AST+LLM pipeline,
  consumption model, stale data mitigation)
- Implementation plan with 6 milestones and rollout strategy
- TypeScript package structure with all source stubs
- CLI entry point, formatter, discover, init, patch, validate, extract, merge
- Pi SKILL.md with tool definitions and format documentation

.gitignore

@@ -0,0 +1,6 @@
+node_modules/
+dist/
+coverage/
+*.log
+.DS_Store
+.env