Using ARG query to support AppConfig resource read operations

[ArthurMa1978]

What does this PR do?

This PR addresses part of the issue tracked in #226 by updating the AppConfig tool to eliminate its dependency on Azure.ResourceManager.AppConfiguration.
As a result, it reduces the MCP agent size by approximately 541 KB.

GitHub issue number?

#226

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
  • Updated command list in /docs/azmcp-commands.md and/or /docs/fabric-commands.md
  • 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 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 /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 refactors the AppConfig tool to use Azure Resource Graph (ARG) queries instead of direct Azure Resource Manager API calls, eliminating the dependency on Azure.ResourceManager.AppConfiguration and reducing the MCP agent size by approximately 541 KB.

Key changes include:

• Replaced direct ARM API calls with ARG queries for resource discovery
• Added custom data models to handle JSON deserialization from ARG responses
• Updated the service to inherit from BaseAzureResourceService for ARG functionality

Reviewed Changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
AppConfigService.cs	Refactored to use ARG queries and added JSON conversion logic
AppConfigurationStoreData.cs	New model for deserializing ARG query responses
AppConfigurationStoreProperties.cs	New model for App Configuration store properties
AppConfigurationStoreEncryptionProperties.cs	New model for encryption settings
AppConfigurationKeyVaultProperties.cs	New model for Key Vault properties
AppConfigurationAccount.cs	Updated property types to be nullable
AppConfigJsonContext.cs	Added JSON serialization context for new models
Azure.Mcp.Tools.AppConfig.csproj	Removed dependency on Azure.ResourceManager.AppConfiguration
AppConfigCommandTests.cs	Updated test constructor to include logger dependency
Directory.Packages.props	Removed package reference
CHANGELOG.md	Documented the refactoring and dependency removal
.vscode/cspell.json	Updated spell checker configuration