[WIP] Add fx-to-dotnet: Migrate support from Framework to Core

[Copilot]

Thanks for asking me to work on this. I will get started on it and keep this PR's description up to date as I form a plan and make progress.

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This section details on the original issue you should resolve

<issue_title>[Extension]: Add fx-to-dotnet: Migrate support from Framework to Core</issue_title>
<issue_description>### Extension ID

fx-to-dotnet

Extension Name

.NET Framework to Modern .NET Migration

Version

0.8.0

Description

Orchestrate end-to-end .NET Framework to modern .NET migration across 7 phases, with SDD lifecycle integration

Author

RogerBestMsft

Repository URL

https://github.com/RogerBestMsft/spec-kit-FxToNet

Download URL

https://github.com/RogerBestMsft/spec-kit-FxToNet/releases/download/v0.8.0/fx-to-dotnet.zip

License

MIT

Homepage (optional)

No response

Documentation URL (optional)

No response

Changelog URL (optional)

No response

Required Spec Kit Version

=0.1.0

Required Tools (optional)

- Microsoft.GitHubCopilot.Modernization.Mcp

Number of Commands

12

Number of Hooks (optional)

5

Tags

• "dotnet"
• "migration"
• "modernization"
• "framework"
• "aspnet"
• "shared-artifact"

Key Features

• Convert project to SDK style
• Review and update packages
• Iterative build and fix

Testing Checklist

• Extension installs successfully via download URL
• All commands execute without errors
• Documentation is complete and accurate
• No security vulnerabilities identified
• Tested on at least one real project

Submission Requirements

• Valid extension.yml manifest included
• README.md with installation and usage instructions
• LICENSE file included
• GitHub release created with version tag
• All command files exist and are properly formatted
• Extension ID follows naming conventions (lowercase-with-hyphens)

Testing Details

Tested on:

• Windows 11
• VSCode Copilot

Test Project:

• Framework solution with multiple projects based on Framework 4.8

Test Scenarios:

1. Installed extension
2. Primary workflow: Constitution, Specify with hook, Plan with hook, Tasks with hook, and Implement
3. Secondary direct extension:

Example Usage

uv tool install specify-cli --from git+https://github.com/github/spec-kit.git
specify init --here --integration copilot
specify extension add fx-to-dotnet --from https://github.com/RogerBestMsft/spec-kit-FxToNet/releases/download/v0.8.0/fx-to-dotnet.zip

/speckit.specify Migrate existing solution
/speckit.plan Migrate <solution path>
/speckit.tasks
/speckit.implement

Proposed Catalog Entry

{
"fx-to-dotnet": {
      "name": ".NET Framework to Modern .NET Migration",
      "id": "fx-to-dotnet",
      "description": "Orchestrate end-to-end .NET Framework to modern .NET migration across 7 phases, with SDD lifecycle integration.",
      "author": "Microsoft",
      "version": "0.8.0",
      "download_url": "https://github.com/RogerBestMsft/spec-kit-FxToNet/releases/download/v0.8.0/fx-to-dotnet.zip",
      "repository": "https://github.com/RogerBestMsft/spec-kit-FxToNet",
      "homepage": "https://github.com/RogerBestMsft/spec-kit-FxToNet",
      "documentation": "https://github.com/RogerBestMsft/spec-kit-FxToNet/blob/main/README.md",
      "license": "MIT",
      "requires": {
        "speckit_version": ">=0.7.2",
        "tools": [
          {
            "name": "Microsoft.GitHubCopilot.Modernization.Mcp",
            "version": ">=0.0.0",
            "required": true
          }
        ]
      },
      "provides": {
        "commands": 12,
        "hooks": 5
      },
      "tags": [
        "dotnet",
        "migration",
        "modernization",
        "aspnet",
        "sdd"
      ],
      "verified": false,
      "downloads": 0,
      "stars": 0,
      "created_at": "2026-05-04T00:00:00Z",
      "updated_at": "2026-05-04T00:00:00Z"
    }
}

Additional Context

No response</issue_description>

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