Add Cloud to telemetry

[alzimmermsft]

What does this PR do?

Adds a new telemetry Cloud to the start of the TelemetryService to indicate which Azure cloud environment the MCP server is using. The Cloud value will be one of the AzureCloud enum values, which are the following at this time:

• AzurePublicCloud
• AzureChinaCloud
• AzureUSGovernmentCloud

GitHub issue number?

[Link to the GitHub issue this PR addresses]

Pre-merge Checklist

• Required for All PRs
  • Read contribution guidelines
  • PR title clearly describes the change
  • Commit history is clean with descriptive messages (cleanup guide)
  • Added comprehensive tests for new/modified functionality
  • Updated servers/Azure.Mcp.Server/CHANGELOG.md and/or servers/Fabric.Mcp.Server/CHANGELOG.md for product changes (features, bug fixes, UI/UX, updated dependencies)
• For MCP tool changes:
  • One tool per PR: This PR adds or modifies only one MCP tool for faster review cycles
  • Updated servers/Azure.Mcp.Server/README.md and/or servers/Fabric.Mcp.Server/README.md documentation
  • Validate README.md changes using script at eng/scripts/Process-PackageReadMe.ps1. See Package README
  • Updated command list in /servers/Azure.Mcp.Server/docs/azmcp-commands.md and/or /docs/fabric-commands.md
  • Run .\eng\scripts\Update-AzCommandsMetadata.ps1 to update tool metadata in azmcp-commands.md (required for CI)
  • For new or modified tool descriptions, ran ToolDescriptionEvaluator and obtained a score of 0.4 or more and a top 3 ranking for all related test prompts
  • For tools with new names, including new tools or renamed tools, update consolidated-tools.json
  • For new tools associated with Azure services or publicly available tools/APIs/products, add URL to documentation in the PR description
• Extra steps for Azure MCP Server tool changes:
  • Updated test prompts in /servers/Azure.Mcp.Server/docs/e2eTestPrompts.md
  • 👉 For Community (non-Microsoft team member) PRs:
    • Security review: Reviewed code for security vulnerabilities, malicious code, or suspicious activities before running tests (crypto mining, spam, data exfiltration, etc.)
    • Manual tests run: added comment /azp run mcp - pullrequest - live to run Live Test Pipeline

[Copilot]

Pull request overview

This PR adds an explicit Cloud tag to the server’s telemetry so emitted activities indicate which Azure cloud environment (Public/China/US Gov/custom authority) the MCP server is using.

Changes:

• Add TagName.Cloud and include it in TelemetryService default tags using AzureCloudConfiguration parsing logic.
• Refactor AzureCloudConfiguration to expose reusable LoadCloudValue and ParseCloudValue helpers (internal) for shared cloud resolution behavior.
• Extend TelemetryServiceTests with new cases validating cloud tag selection from ServiceStartOptions and IConfiguration.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
servers/Azure.Mcp.Server/changelog-entries/1772564548835.yaml	Adds changelog entry documenting the telemetry change.
core/Microsoft.Mcp.Core/tests/Microsoft.Mcp.Core.UnitTests/Services/Telemetry/TelemetryServiceTests.cs	Adds/updates unit tests to assert Cloud tagging behavior.
core/Microsoft.Mcp.Core/src/Services/Telemetry/TelemetryService.cs	Adds Cloud tag computation and injection of IConfiguration.
core/Microsoft.Mcp.Core/src/Services/Azure/Authentication/AzureCloudConfiguration.cs	Extracts cloud-value load/parse logic into internal helpers.
core/Microsoft.Mcp.Core/src/Commands/TelemetryConstants.cs	Introduces the Cloud telemetry tag name constant.