MCP instrumentation (ADOT) disabled by default while agent instrumentation is enabled

## Description

Agent instrumentation via ADOT is enabled by default, but MCP instrumentation via ADOT is disabled by default. This inconsistency means users miss MCP-level observability unless they manually enable it.

## Steps to Reproduce

1. Deploy an agent with MCP tools configured
2. Check ADOT instrumentation settings
3. Observe that agent instrumentation is enabled but MCP instrumentation is not

## Expected Behavior

MCP instrumentation (ADOT) should be enabled by default, consistent with agent instrumentation behavior.

## Actual Behavior

MCP instrumentation (ADOT) is disabled by default. Users must manually enable it.

## CLI Version

_N/A_

## Operating System

macOS