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/hooks/useClientConfig.ts

@@ -18,6 +18,7 @@ export type ClientConfig = {
   };
 
   hashRouter?: HashRouterConfig;
+  gifApiKey?: string;
 };
 
 const ClientConfigContext = createContext<ClientConfig | null>(null);