chore: set telemetry app name if not set or is vscode MCP-131

[himanshusinghs]

Description

Sets the appName parameter in connection string to the following format {default vscode appname} MongoDB MCP Server when:

• appName is not set
• appName is set to default VSCode's app name

and extend that VSCode specific extended app name format ${appName}--${telemetryAnonymousId}--${connectionId}

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)