Two broken-access-control holes:
- PUT/DELETE /files/:id/tags(/:tag_id) and GET /files/:id/tags went
straight to TagService with no ACL check, letting any authenticated
user read or rewrite tags on anyone's private files. The handlers now
require view (list) or edit (mutate) on the target file via new
FileService.AuthorizeView/AuthorizeEdit helpers.
- POST /files/import accepted an arbitrary host path from any user,
turning it into an arbitrary server-side file read. It is now
admin-only and the supplied path is confined to IMPORT_PATH.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>