UX: reset progress, per module and all

Part of the UX backlog. Raised on 2026-06-11, where it was noted as "pending API storage" — that blocker is gone, since progress is local.

There is currently no way to reset progress. A reader who wants to start over, or who clicked through a module without reading it, is stuck with the state.

Scope

• Reset a single module's progress
• Reset everything

Progress lives entirely in localStorage under the course_progress key (lib/progress.ts), so this is a small, self-contained change — add reset functions there and expose them in the UI.

Where

lib/progress.ts, plus an entry point in components/ModulePlayerClient.tsx (per module) and somewhere on the catalog (reset all).

Watch out

Resetting everything is destructive and unrecoverable — there is no server copy. It needs a confirmation step.

Done when

Both resets work, survive a reload, and the destructive one asks first.

Start in lib/progress.ts and trace how the course_progress localStorage key is read and written. Then inspect components/ModulePlayerClient.tsx for the per-module entry point and the catalog for the reset-all entry point. Done means both resets persist after reload, with confirmation before the destructive reset.