Fix the null value assignment in GetValueOrDefault()

[ericshape]

What does this PR do?

Fix the null value assignment in GetValueOrDefault()
context: #437 (comment)

when the optional value passed in var options = BindOptions(parseResult); it will directly assign long? to 0, int? to 0, and bool? to false. however, they are null optional values.

i.e. when I run 'azmcp sql db create -subscription sub --resource-group rg --server server1 --database testdb'

the GetValueOrDefault will auto assign optional values:

long? --max-size-bytes to 0,
int? sku-capacity to 0,
and bool? --zone-redundan to false

this bug fix is blocking #434

GitHub issue number?

#437

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
• 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 fixes a bug in the GetValueOrDefault() method where optional nullable values were incorrectly being assigned default values (0 for int/long, false for bool) instead of null when not explicitly provided by the user.

• Improves the HasOptionResult() method to properly handle bool options as switches or with explicit values
• Updates GetValueOrDefault() to check if an option was explicitly provided before returning values
• Adds comprehensive test coverage for the fixed behavior across different nullable types

Reviewed Changes

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

File	Description
CommandResultExtensions.cs	Enhanced option presence detection and fixed null value assignment logic
CommandResultExtensionsTests.cs	Added comprehensive test coverage for nullable options with explicit and missing values

[ericshape]

once the review is done, I will add fix description into Changelog md file.
Changelog file is easy to have conflicts. I will add before merge

[jongio]

/azp run mcp - pullrequest - live

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[ericshape]

/azp run mcp - pullrequest - live

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).