Backend now supports order=latest on GET /api/sessions/{id}/messages
(offset measured back from the newest message, page returned
chronologically). The mobile initial load previously computed its anchor
from a possibly-stale session-list message_count, which landed the first
page at the wrong position (dropped history or a duplicated tail).
- HermesApiService.getSessionMessages: add @Query("order")
- Initial load requests the newest page directly (order=latest, offset=0)
and drops the fetchServerMessageCount offset math; legacy backends
(no pagination echo) fall back to the count-based anchor
- Backward paging advances the from-end offset by a full page; a short
page marks the oldest boundary and stops pagination
- ChatMessage stable keys under latest paging use the server's
AUTOINCREMENT row id (from-end positions shift as the transcript
grows and would collide across hydrations)
- syncCurrentSession refetches the newest page and merges by row id
with a logical-content fallback for re-keyed rows
Co-authored-by: M57 <hy4ri@users.noreply.github.com>
