Migrate AKS tools to new tool design

[alzimmermsft]

What does this PR do?

Migrates AKS tools to new design where Register and Bind options are based on Option attributes.

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
  • Created a changelog entry if the change falls among the following: new feature, bug fix, UI/UX update, breaking change, or updated dependencies. Follow the changelog entry guide
• 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 running the script ./eng/scripts/Process-PackageReadMe.ps1. See Package README
  • 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 renamed tools, follow the Tool Rename Checklist and tag the PR with the breaking-change label
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• Extra steps for Azure MCP Server tool changes:
  • Updated command list in servers/Azure.Mcp.Server/docs/azmcp-commands.md
  • Ran ./eng/scripts/Update-AzCommandsMetadata.ps1 to update tool metadata in azmcp-commands.md (required for CI)
  • 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 migrates the AKS tool commands and options to the newer attribute-driven option model (via [Option] attributes) and aligns AKS commands with the shared SubscriptionCommand<,> base in Azure.Mcp.Core.

Changes:

• Converted ClusterGet and NodepoolGet options to POCOs using [Option] attributes and ISubscriptionOption instead of System.CommandLine option registration/binding.
• Updated AKS get commands to derive from SubscriptionCommand<,> and accept ISubscriptionResolver for subscription resolution.
• Updated corresponding unit tests to use SubscriptionCommandUnitTestsBase and removed AKS-specific command/option base types.

Reviewed changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tools/Azure.Mcp.Tools.Aks/tests/Azure.Mcp.Tools.Aks.Tests/Nodepool/NodepoolGetCommandTests.cs	Switches tests to the subscription-aware command unit test base for the new command shape.
tools/Azure.Mcp.Tools.Aks/tests/Azure.Mcp.Tools.Aks.Tests/Cluster/ClusterGetCommandTests.cs	Updates tests for the new options-binding model and subscription resolver injection.
tools/Azure.Mcp.Tools.Aks/src/Options/Nodepool/NodepoolGetOptions.cs	Replaces JSON-property-based options with [Option] attribute-based options for nodepool get.
tools/Azure.Mcp.Tools.Aks/src/Options/Cluster/ClusterGetOptions.cs	Replaces JSON-property-based options with [Option] attribute-based options for cluster get.
tools/Azure.Mcp.Tools.Aks/src/Options/BaseAksOptions.cs	Removes the AKS-specific options base class (no longer needed with the new option model).
tools/Azure.Mcp.Tools.Aks/src/Options/AksOptionDefinitions.cs	Removes legacy System.CommandLine option definitions used by the previous design.
tools/Azure.Mcp.Tools.Aks/src/GlobalUsings.cs	Removes the AKS tool’s global System.CommandLine import (no longer used by migrated commands).
tools/Azure.Mcp.Tools.Aks/src/Commands/Nodepool/NodepoolGetCommand.cs	Migrates nodepool get command to SubscriptionCommand<,> and options POCO binding.
tools/Azure.Mcp.Tools.Aks/src/Commands/Cluster/ClusterGetCommand.cs	Migrates cluster get command to SubscriptionCommand<,> and options POCO binding (adds custom validation).
tools/Azure.Mcp.Tools.Aks/src/Commands/BaseAksCommand.cs	Removes the AKS-specific command base type in favor of the shared subscription base.
core/Azure.Mcp.Core/src/Commands/Subscription/SubscriptionCommand`2.cs	Refactors subscription command base to a primary-constructor pattern for resolver injection.