feat(messages): enhance message and edit history with channel names and content diffs

services/frontend/src/lib/types/knowledge.ts

@@ -18,6 +18,7 @@ export interface EditHistoryRow {
   id: string;
   message_id: string;
   old_content: string;
+  new_content: string;
   edited_at: number;
   channel_id: string | null;
   channel_name: string | null;

services/frontend/src/lib/types/message.ts

@@ -175,6 +175,7 @@ export interface SemanticSearchResult {
 
 export interface MessageActivityBucket {
   channelId: string;
+  channelName: string;
   hour: number;
   count: number;
 }