- add util.Go with panic recovery for background goroutines
- add util.EscapeLike and explicit ESCAPE clause for SQL LIKE queries
- add DummyCheckPassword and subtle.ConstantTimeCompare against timing attacks
- enforce session ID rotation upon login/oauth callback to prevent session fixation
- add sliding window login failure rate limiting and oauth state rate limiting
- fix redis client capture race in pubsub listeners and wait on stop channel
- adjust global --primary to oklch(51.1% 0.262 276.966) for WCAG AA contrast
- fix semantic heading levels and missing aria-labels across UI components
- document security, concurrency, and a11y standards in AGENTS.md
- Expose user-scoped CRUD APIs under `/api/v1/upload` (my files query, stats, rename, delete)
- Update backend handlers and routers with ownership validation checks
- Create a dedicated frontend personal file manager card-list and upload button under `/files`
- Add comprehensive backend test coverage and update API docs
- Remove file list, stats, download, and deletion routes from '/api/v1/upload'
- Move these endpoints under '/api/v1/admin/uploads'
- Remove user-specific filtering from files query and statistics to aggregate system-wide uploads by default
- Allow admins to bypass ownership check when downloading private files
- Update backend unit tests, Swagger documentation, and frontend service client and components
ryan