v2.0.0

release: v2.0.0 — the final state

APP_VERSION 2.0.0 (versioned PWA cache + update banner baseline).
ROADMAP §0 definition of done is fully shipped: one-file install,
zip/folder import, per-chat analytics + windowed findings under their
charts, connected profile with every metric range-aware, compare mode,
hide/merge/profiles, update awareness, phone-browser dashboard + PWA.
Maintenance mode from here; new ideas go to the POST_2.0 parking lot.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>