feat: poll voting, location sharing, image captions, message forwarding

- Poll voting: PollContent sends m.poll.response on answer click
- Location: MLocation shows OSM map embed + share-location button in toolbar
- Image captions: caption field on media uploads sets message body
- Message forwarding: ForwardMessageDialog with searchable room picker
- Also includes ring timeout fix and earlier session patches

src/app/state/room/roomInputDrafts.ts

@@ -9,6 +9,7 @@ import { createListAtom } from '../list';
 
 export type TUploadMetadata = {
   markedAsSpoiler: boolean;
+  caption?: string;
 };
 
 export type TUploadItem = {