feat: add target repo examples and file layout guidance

examples/go-project/ai/project-map.md

@@ -0,0 +1,10 @@
+# Project Map
+
+## Main structure
+- `cmd/` contains runnable binaries
+- `internal/` contains non-exported app logic
+- `pkg/` is for reusable public packages if present
+
+## Notes
+- Check `Makefile` for repo-preferred command wrappers
+- Some integration tests may depend on Docker or local services