feat: bootstrap design kit and vaporwave demo baseline

VERSIONING.md

@@ -0,0 +1,24 @@
+# Versioning Policy
+
+This repository uses `v0.x.y` tags while the public bundle contracts are stabilizing.
+
+## Public Compatibility Surface
+
+Breaking changes are changes to:
+
+- `kit/` file paths or template variables
+- `exports/` manifest schema or bundle ids
+- `tools/designsync` CLI behavior/flags
+
+## Tagging Rules (`v0.x.y`)
+
+- `y` (patch): fixes, docs updates, non-breaking improvements
+- `x` (minor): any breaking public-surface change during `0.x`
+
+## Release Checklist
+
+1. Update `CHANGELOG.md`
+2. Validate manifests (`designsync validate`)
+3. Run tests (`go test ./...` and `cd demo && go test ./...`)
+4. Tag release
+