Adds broad coverage across stores, hooks, and runtime utilities while switching `vitest.config.ts` to an explicit whole-repo include list. This turns the coverage report into a real repo-wide baseline instead of an imported-file subset.
Added `useFileUpload()` and `uploadToCatbox()` to centralize upload behavior and remove duplicated upload code from `post-form.tsx` and `reply-modal.tsx`. The flow now routes Android to `FileUploader`, Electron to hidden-input + catbox upload, and web to a translated fallback alert with consistent upload UI state.
plebeius