feat: add Pi conversation worker pool

electron/coding-projects/conversation-store.ts

@@ -213,6 +213,28 @@ export function createCodingConversationStore(
       });
     },
 
+    async setModelState(
+      conversationId: string,
+      modelState: ConversationModelState,
+    ): Promise<CodingConversationV2> {
+      return await mutate(async (file) => {
+        const current = file.conversations.find((item) => item.id === conversationId);
+        if (!current) throw new Error('Conversation does not exist');
+        const updated = normalizeConversation({
+          ...current,
+          ...modelState,
+          updatedAt: now(),
+        });
+        return {
+          result: updated,
+          file: {
+            schemaVersion: 2,
+            conversations: file.conversations.map((item) => item.id === conversationId ? updated : item),
+          },
+        };
+      });
+    },
+
     async ensureSessionBinding(
       conversationId: string,
       createBinding: () => Promise<PiSessionBinding>,