feat(telemetry): Implement AI usage telemetry pattern and apply to add-task

This commit introduces a standardized pattern for capturing and propagating AI usage telemetry (cost, tokens, model used) across the Task Master stack and applies it to the 'add-task' functionality.

Key changes include:

- **Telemetry Pattern Definition:**
  - Added  defining the integration pattern for core logic, direct functions, MCP tools, and CLI commands.
  - Updated related rules (, ,
 Usage: mcp [OPTIONS] COMMAND [ARGS]...

 MCP development tools

╭─ Options ──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│ --help          Show this message and exit.                                                                                                │
╰────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯
╭─ Commands ─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│ version   Show the MCP version.                                                                                                            │
│ dev       Run a MCP server with the MCP Inspector.                                                                                         │
│ run       Run a MCP server.                                                                                                                │
│ install   Install a MCP server in the Claude desktop app.                                                                                  │
╰────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯, , ) to reference the new telemetry rule.

- **Core Telemetry Implementation ():**
  - Refactored the unified AI service to generate and return a  object alongside the main AI result.
  - Fixed an MCP server startup crash by removing redundant local loading of  and instead using the  imported from  for cost calculations.
  - Added  to the  object.

- ** Integration:**
  - Modified  (core) to receive  from the AI service, return it, and call the new UI display function for CLI output.
  - Updated  to receive  from the core function and include it in the  payload of its response.
  - Ensured  (MCP tool) correctly passes the  through via .
  - Updated  to correctly pass context (, ) to the core  function and rely on it for CLI telemetry display.

- **UI Enhancement:**
  - Added  function to  to show telemetry details in the CLI.

- **Project Management:**
  - Added subtasks 77.6 through 77.12 to track the rollout of this telemetry pattern to other AI-powered commands (, , , , , , ).

This establishes the foundation for tracking AI usage across the application.

mcp-server/src/core/direct-functions/add-task.js

@@ -94,6 +94,7 @@ export async function addTaskDirect(args, log, context = {}) {
 
 		let manualTaskData = null;
 		let newTaskId;
+		let telemetryData;
 
 		if (isManualCreation) {
 			// Create manual task data object
@@ -109,7 +110,7 @@ export async function addTaskDirect(args, log, context = {}) {
 			);
 
 			// Call the addTask function with manual task data
-			newTaskId = await addTask(
+			const result = await addTask(
 				tasksPath,
 				null, // prompt is null for manual creation
 				taskDependencies,
@@ -117,13 +118,17 @@ export async function addTaskDirect(args, log, context = {}) {
 				{
 					session,
 					mcpLog,
-					projectRoot
+					projectRoot,
+					commandName: 'add-task',
+					outputType: 'mcp'
 				},
 				'json', // outputFormat
 				manualTaskData, // Pass the manual task data
 				false, // research flag is false for manual creation
 				projectRoot // Pass projectRoot
 			);
+			newTaskId = result.newTaskId;
+			telemetryData = result.telemetryData;
 		} else {
 			// AI-driven task creation
 			log.info(
@@ -131,7 +136,7 @@ export async function addTaskDirect(args, log, context = {}) {
 			);
 
 			// Call the addTask function, passing the research flag
-			newTaskId = await addTask(
+			const result = await addTask(
 				tasksPath,
 				prompt, // Use the prompt for AI creation
 				taskDependencies,
@@ -139,12 +144,16 @@ export async function addTaskDirect(args, log, context = {}) {
 				{
 					session,
 					mcpLog,
-					projectRoot
+					projectRoot,
+					commandName: 'add-task',
+					outputType: 'mcp'
 				},
 				'json', // outputFormat
 				null, // manualTaskData is null for AI creation
 				research // Pass the research flag
 			);
+			newTaskId = result.newTaskId;
+			telemetryData = result.telemetryData;
 		}
 
 		// Restore normal logging
@@ -154,7 +163,8 @@ export async function addTaskDirect(args, log, context = {}) {
 			success: true,
 			data: {
 				taskId: newTaskId,
-				message: `Successfully added new task #${newTaskId}`
+				message: `Successfully added new task #${newTaskId}`,
+				telemetryData: telemetryData
 			}
 		};
 	} catch (error) {