feat: implement expand-task MCP command

- Create direct function wrapper in expand-task.js with error handling

- Add MCP tool integration for breaking down tasks into subtasks

- Update task-master-core.js to expose expandTaskDirect function

- Update changeset to document the new command

- Parameter support for subtask generation options (num, research, prompt, force)

tasks/task_023.txt

@@ -538,7 +538,7 @@ Following MCP implementation standards:
    - Unit test for showTaskDirect.js
    - Integration test for MCP tool
 
-## 23. Implement next-task MCP command [in-progress]
+## 23. Implement next-task MCP command [done]
 ### Dependencies: None
 ### Description: Create direct function wrapper and MCP tool for finding the next task to work on.
 ### Details:
@@ -571,7 +571,7 @@ Following MCP implementation standards:
    - Unit test for nextTaskDirect.js
    - Integration test for MCP tool
 
-## 24. Implement expand-task MCP command [pending]
+## 24. Implement expand-task MCP command [done]
 ### Dependencies: None
 ### Description: Create direct function wrapper and MCP tool for expanding a task into subtasks.
 ### Details:

tasks/tasks.json

@@ -1555,7 +1555,7 @@
           "title": "Implement next-task MCP command",
           "description": "Create direct function wrapper and MCP tool for finding the next task to work on.",
           "details": "Following MCP implementation standards:\n\n1. Create nextTaskDirect.js in mcp-server/src/core/direct-functions/:\n   - Import nextTask from task-manager.js\n   - Handle file paths using findTasksJsonPath utility\n   - Process arguments (no specific args needed except projectRoot/file)\n   - Handle errors with try/catch\n   - Return standardized { success, data/error } object\n\n2. Export from task-master-core.js:\n   - Import the function from its file\n   - Add to directFunctions map\n\n3. Create next-task.js MCP tool in mcp-server/src/tools/:\n   - Import z from zod for parameter schema\n   - Import executeMCPToolAction from ./utils.js\n   - Import nextTaskDirect from task-master-core.js\n   - Define parameters matching CLI options using zod schema\n   - Implement registerNextTaskTool(server) with server.addTool\n   - Use executeMCPToolAction in execute method\n\n4. Register in tools/index.js with tool name 'next_task'\n\n5. Add to .cursor/mcp.json with appropriate schema\n\n6. Write tests following testing guidelines:\n   - Unit test for nextTaskDirect.js\n   - Integration test for MCP tool",
-          "status": "in-progress",
+          "status": "done",
           "dependencies": [],
           "parentTaskId": 23
         },
@@ -1564,7 +1564,7 @@
           "title": "Implement expand-task MCP command",
           "description": "Create direct function wrapper and MCP tool for expanding a task into subtasks.",
           "details": "Following MCP implementation standards:\n\n1. Create expandTaskDirect.js in mcp-server/src/core/direct-functions/:\n   - Import expandTask from task-manager.js\n   - Handle file paths using findTasksJsonPath utility\n   - Process arguments: taskId, prompt, num, force, research\n   - Validate inputs and handle errors with try/catch\n   - Return standardized { success, data/error } object\n\n2. Export from task-master-core.js:\n   - Import the function from its file\n   - Add to directFunctions map\n\n3. Create expand-task.js MCP tool in mcp-server/src/tools/:\n   - Import z from zod for parameter schema\n   - Import executeMCPToolAction from ./utils.js\n   - Import expandTaskDirect from task-master-core.js\n   - Define parameters matching CLI options using zod schema\n   - Implement registerExpandTaskTool(server) with server.addTool\n   - Use executeMCPToolAction in execute method\n\n4. Register in tools/index.js with tool name 'expand_task'\n\n5. Add to .cursor/mcp.json with appropriate schema\n\n6. Write tests following testing guidelines:\n   - Unit test for expandTaskDirect.js\n   - Integration test for MCP tool",
-          "status": "pending",
+          "status": "done",
           "dependencies": [],
           "parentTaskId": 23
         },