- Merge structural lint rules into oxlint.json and remove the second config file
- Add #tests/* path aliases and rewrite deep test helper imports
- Ban new deep parent-relative imports through the shared lint config
- Move multi-selection.test.ts into focused flip, alignment, and property files
- Reuse scene and assertion helpers for selection tests
- Preserve all 22 multi-selection tests and enforce non-null assertion cleanup on the new folder
- Move clipboard.test.ts into focused import, bounds, HTML encoding, and fixture roundtrip files
- Add a shared clipboard graph helper for import tests
- Preserve all 29 clipboard tests after the split
