Chats 0.20.1 (dev) — shared store + sync-health fixes — R8 APK (23 MB)

• Line switches keep your session: dev now uses the same session store as main (filesDir/matrix_client.db, one-time legacy copy from databases/) — switching between the Tool Library line and dev no longer logs you out (the 2026-10-25 LP3 swap kill). Building on this store requires a fresh login once; afterwards it persists across both lines.
• Account screen "Message sync status": the screen-on long-poll loop now stamps delivery health — the row no longer read "never synced" while sync was actively running; "just now" wording matches main.
• Also carries the R8 keep-rule fix for optional netty-tcnative/JFR/log4j/BlockHound deps (release builds were failing :tool:minifyReleaseWithR8 after the SDK netty bump).