Drain before autofetch, fix same-second collisions, and always mc.disconnect() on false/probe failure

frontend/src/hooks/useConversationMessages.ts

@@ -50,7 +50,11 @@ function mergePendingAck(
 
 // Generate a key for deduplicating messages by content
 export function getMessageContentKey(msg: Message): string {
-  return `${msg.type}-${msg.conversation_key}-${msg.text}-${msg.sender_timestamp}`;
+  // When sender_timestamp exists, dedup by content (catches radio-path duplicates with different IDs).
+  // When null, include msg.id so each message gets a unique key — avoids silently dropping
+  // different messages that share the same text and received_at second.
+  const ts = msg.sender_timestamp ?? `r${msg.received_at}-${msg.id}`;
+  return `${msg.type}-${msg.conversation_key}-${msg.text}-${ts}`;
 }
 
 export interface UseConversationMessagesResult {