refactor(ChatMessagesPane): extract message key generation logic to a utility function

src/components/chat/utils/messageKeys.ts

@@ -0,0 +1,38 @@
+import type { ChatMessage } from '../types/types';
+
+const toMessageKeyPart = (value: unknown): string | null => {
+  if (typeof value !== 'string' && typeof value !== 'number') {
+    return null;
+  }
+
+  const normalized = String(value).trim();
+  return normalized.length > 0 ? normalized : null;
+};
+
+export const getIntrinsicMessageKey = (message: ChatMessage): string | null => {
+  const candidates = [
+    message.id,
+    message.messageId,
+    message.toolId,
+    message.toolCallId,
+    message.blobId,
+    message.rowid,
+    message.sequence,
+  ];
+
+  for (const candidate of candidates) {
+    const keyPart = toMessageKeyPart(candidate);
+    if (keyPart) {
+      return `message-${message.type}-${keyPart}`;
+    }
+  }
+
+  const timestamp = new Date(message.timestamp).getTime();
+  if (!Number.isFinite(timestamp)) {
+    return null;
+  }
+
+  const contentPreview = typeof message.content === 'string' ? message.content.slice(0, 48) : '';
+  const toolName = typeof message.toolName === 'string' ? message.toolName : '';
+  return `message-${message.type}-${timestamp}-${toolName}-${contentPreview}`;
+};