v0.1.7 — briefing dismiss + Agent panel + sync-flush perf

Briefing dismiss → blank inbox
Clicking 'Got it — open inbox' now lands you on Priority (where the briefed action items live), not the empty Other tab. Default split for new sessions is now All instead of the structurally-empty Other.

Agent panel
The Agents sidebar shows a clear 'Inbox Agent runs automatically' V1 summary instead of 'No agents available.' Manage button routes to Settings → Agents specifically.

Sync-flush perf
Three no-op short-circuits on the renderer hot path. Background sync re-emissions of unchanged data no longer trigger O(N) groupByThread recomputes over 2500+ emails. Steady-state polling cycles should feel snappier.