fix: chat accepts posts

components/chat/share-to-chat-dialog.tsx

@@ -37,12 +37,16 @@ type SendState = "idle" | "sending" | "sent";
 export function ShareToChatDialog({
   body = "",
   quote,
+  entity,
   onClose,
 }: {
   /** Plain message text. Empty when sending a quote on its own. */
   body?: string;
   /** A passage from the library, sent as a tappable quotation. */
   quote?: QuotePayload;
+  /** A post, sent as a card. Only the reference travels — the BFF resolves
+   *  the contents and re-checks visibility for each viewer. */
+  entity?: { type: "post"; id: string };
   onClose: () => void;
 }) {
   const { user } = useAuth();
@@ -111,7 +115,7 @@ export function ShareToChatDialog({
     mark(handle, "sending");
     try {
       const id = conversationId ?? (await chat.openDM(handle)).id;
-      await chat.send(id, body, { quote });
+      await chat.send(id, body, { quote, entity });
       mark(handle, "sent");
     } catch {
       mark(handle, "idle");