## Refactor app-dev state management and build utilities
- Store only `manifest` in `AppDevState` instead of full
`ManifestBuildResult`; add `sourcePath` to `FileStatus`
- Pass `sourcePaths` directly to watchers instead of
`ManifestBuildResult`
- Only reset `fileUploadStatus` for functions/components when their
source paths change
- Add pure `updateManifestChecksum` utility that returns a new manifest
without side effects
- Extract `processEsbuildResult` to deduplicate build result processing
between watchers
- Rename `serverlessFunctions` → `functions` in SDK code (API unchanged)
- Extract `writeManifestToOutput` to shared `manifest-writer.ts`
Charles Bochet
210c66b5dd