fix: add hosting_mode to mcp telemetry

[nirinchev]

Description

Checklist

• New tests and/or benchmarks are included
• Documentation is changed or added
• I have signed the MongoDB Contributor License Agreement (https://www.mongodb.com/legal/contributor-agreement)

Motivation and Context

• Bugfix
• New feature
• Dependency update
• Misc

Open Questions

Dependents

Types of changes

• Backport Needed
• Patch (non-breaking change which fixes an issue)
• Minor (non-breaking change which adds functionality)
• Major (fix or feature that would cause existing functionality to change)

[Copilot]

Pull Request Overview

This PR adds telemetry tracking to the MCP (Model Context Protocol) controller by including a hosting_mode property to identify when MCP is running within a VS Code extension context.

• Adds hosting_mode: 'vscode-extension' to MCP telemetry properties

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