Open chat on the newest message and keep it pinned

CURRENT.md

@@ -40,6 +40,13 @@ mobile draft at 390px.
   - [x] C11 preview caching: Discord-hosted image/GIF previews (WebP 320px, hash-addressed, 5 MiB
     cap, one attempt) run after every walk in both modes. Live run `...-20260916090722`:
     `previewed: 2`; thumbs served over `/api/media/<scrape>/<item>/thumb` (200).
+  - [x] C78 Chat starts on the newest message. `renderMessages` pins the scroll when the channel
+    changes or the user is already at the bottom, re-pins on the next frame and after 120/400 ms,
+    and re-pins on late image loads while pinned. `overflow-anchor: none` on `.vk-message-scroll`
+    stops Chrome's anchoring from dragging the view off the bottom. A user who scrolled up stays
+    put across re-renders, the mobile chat tab re-pins when it becomes visible, and opening a guild
+    channel or DM lands on the newest message. Verified in a browser across all six cases; the UI
+    smoke test passes. A future jump-to-message link must set `state.messagesPinned = false`.
   - [x] C77 Split user audio investigation. [docs/voice-audio-split.md](docs/voice-audio-split.md)
     records that the daemon sees only the mixed client output (`VeskslopCapture.monitor` → VAD →
     STT) and that per-user tracks exist only in the renderer as WebRTC `MediaStreamTrack`s. The