feat(move-tasks): Implement move command for tasks and subtasks

Adds a new CLI command and MCP tool to reorganize tasks and subtasks within the hierarchy. Features include:
- Moving tasks between different positions in the task list
- Converting tasks to subtasks and vice versa
- Moving subtasks between parents
- Moving multiple tasks at once with comma-separated IDs
- Creating placeholder tasks when moving to new IDs
- Validation to prevent accidental data loss

This is particularly useful for resolving merge conflicts when multiple team members create tasks on different branches.

mcp-server/src/tools/move-task.js

@@ -0,0 +1,124 @@
+/**
+ * tools/move-task.js
+ * Tool for moving tasks or subtasks to a new position
+ */
+
+import { z } from 'zod';
+import {
+	handleApiResult,
+	createErrorResponse,
+	withNormalizedProjectRoot
+} from './utils.js';
+import { moveTaskDirect } from '../core/task-master-core.js';
+import { findTasksJsonPath } from '../core/utils/path-utils.js';
+
+/**
+ * Register the moveTask tool with the MCP server
+ * @param {Object} server - FastMCP server instance
+ */
+export function registerMoveTaskTool(server) {
+	server.addTool({
+		name: 'move_task',
+		description: 'Move a task or subtask to a new position',
+		parameters: z.object({
+			from: z.string().describe(
+				'ID of the task/subtask to move (e.g., "5" or "5.2"). Can be comma-separated to move multiple tasks (e.g., "5,6,7")'
+			),
+			to: z.string().describe(
+				'ID of the destination (e.g., "7" or "7.3"). Must match the number of source IDs if comma-separated'
+			),
+			file: z
+				.string()
+				.optional()
+				.describe('Custom path to tasks.json file'),
+			projectRoot: z
+				.string()
+				.optional()
+				.describe('Root directory of the project (typically derived from session)')
+		}),
+		execute: withNormalizedProjectRoot(async (args, { log, session }) => {
+			try {
+				// Find tasks.json path if not provided
+				let tasksJsonPath = args.file;
+				
+				if (!tasksJsonPath) {
+					tasksJsonPath = findTasksJsonPath(args, log);
+				}
+
+				// Parse comma-separated IDs
+				const fromIds = args.from.split(',').map(id => id.trim());
+				const toIds = args.to.split(',').map(id => id.trim());
+
+				// Validate matching IDs count
+				if (fromIds.length !== toIds.length) {
+					return createErrorResponse(
+						'The number of source and destination IDs must match',
+						'MISMATCHED_ID_COUNT'
+					);
+				}
+
+				// If moving multiple tasks
+				if (fromIds.length > 1) {
+					const results = [];
+					// Move tasks one by one, only generate files on the last move
+					for (let i = 0; i < fromIds.length; i++) {
+						const fromId = fromIds[i];
+						const toId = toIds[i];
+						
+						// Skip if source and destination are the same
+						if (fromId === toId) {
+							log.info(`Skipping ${fromId} -> ${toId} (same ID)`);
+							continue;
+						}
+						
+						const shouldGenerateFiles = i === fromIds.length - 1;
+						const result = await moveTaskDirect(
+							{
+								sourceId: fromId,
+								destinationId: toId,
+								tasksJsonPath,
+								projectRoot: args.projectRoot
+							},
+							log,
+							{ session }
+						);
+						
+						if (!result.success) {
+							log.error(`Failed to move ${fromId} to ${toId}: ${result.error.message}`);
+						} else {
+							results.push(result.data);
+						}
+					}
+					
+					return {
+						success: true,
+						data: {
+							moves: results,
+							message: `Successfully moved ${results.length} tasks`
+						}
+					};
+				} else {
+					// Moving a single task
+					return handleApiResult(
+						await moveTaskDirect(
+							{
+								sourceId: args.from,
+								destinationId: args.to,
+								tasksJsonPath,
+								projectRoot: args.projectRoot
+							},
+							log,
+							{ session }
+						),
+						log
+					);
+				}
+			} catch (error) {
+				return createErrorResponse(
+					`Failed to move task: ${error.message}`,
+					'MOVE_TASK_ERROR'
+				);
+			}
+		})
+	});
+}