feat: show changed files after completed turns

Add changed-file pills with per-file diff stats
Add a chat setting to disable the feature fully
Avoid changed-file projection work when disabled

packages/ui/src/components/chat/message/renderCompare.ts

@@ -1,5 +1,5 @@
 import type { Message, Part } from '@opencode-ai/sdk/v2';
-import type { TurnActivityGroup, TurnActivityRecord, TurnDiffStats, TurnGroupingContext } from '../lib/turns/types';
+import type { TurnActivityGroup, TurnActivityRecord, TurnChangedFile, TurnDiffStats, TurnGroupingContext } from '../lib/turns/types';
 
 type MessageRecord = {
   info: Message;
@@ -146,6 +146,24 @@ const areTurnDiffStatsEqual = (left?: TurnDiffStats, right?: TurnDiffStats): boo
     && left.files === right.files;
 };
 
+const areTurnChangedFilesEqual = (left?: TurnChangedFile[], right?: TurnChangedFile[]): boolean => {
+  if (left === right) return true;
+  if (!left || !right) return !left && !right;
+  if (left.length !== right.length) return false;
+  for (let index = 0; index < left.length; index += 1) {
+    const leftFile = left[index];
+    const rightFile = right[index];
+    if (
+      leftFile.file !== rightFile.file
+      || leftFile.additions !== rightFile.additions
+      || leftFile.deletions !== rightFile.deletions
+    ) {
+      return false;
+    }
+  }
+  return true;
+};
+
 const areTurnActivityRecordsEqual = (left: TurnActivityRecord, right: TurnActivityRecord): boolean => {
   return left.id === right.id
     && left.messageId === right.messageId
@@ -301,5 +319,9 @@ export const areRelevantTurnGroupingContextsEqual = (
     return false;
   }
 
+  if ((ownerRelevant || segmentsRelevant || left.isLastAssistantInTurn || right.isLastAssistantInTurn) && !areTurnChangedFilesEqual(left.changedFiles, right.changedFiles)) {
+    return false;
+  }
+
   return true;
 };