**Add Multi-Platform Build and Signing Support for VS Code Python Debugger Extension**

[bschnurr]

Summary

This PR introduces comprehensive multi-platform build, signing, and publishing support for the Python Debugger extension, along with improvements to how debugpy dependencies are downloaded during the build process.

Key Changes

🏗️ Multi-Platform Build Pipeline

• Added support for building platform-specific VSIX packages for:
  • linux-x64, linux-arm64, linux-armhf
  • darwin-x64, darwin-arm64
  • win32-x64, win32-arm64
  • Universal (platform-agnostic)
• Created new reusable templates:
  • package.yml - Handles multi-platform build matrix with per-platform jobs
  • publish-extension.yml - Orchestrates signing, GitHub releases, and marketplace publishing
  • createGitHubRelease.yml - Automates GitHub release creation
  • modify-extension-version.yml - Manages extension versioning
  • setup.yml - Common setup steps (Node.js, Python, npm auth)

🔐 Enhanced Signing Pipeline

• Refactored sign.yml to support signing multiple platform-specific VSIX files
• Each platform gets its own subfolder to avoid filename collisions
• Added detailed logging and validation steps for signing operations
• Updated sign.proj to support the new directory structure

📦 Improved Dependency Management (noxfile.py)

• Replaced direct URL downloads with pip download for fetching debugpy wheels
• New download_debugpy_via_pip() function respects pip configuration (proxy, internal index/mirror, certs)
• Added _parse_wheel_info() to extract version and platform info from wheel URLs
• Enables builds in environments that cannot access files.pythonhosted.org directly

🚀 Publishing Improvements

• Separated Build and Publish into distinct pipeline stages
• Added GitHub release creation with automatic tagging (v{version})
• Updated publish.yml to handle multi-platform artifact publishing
• Support for both pre-release and stable release workflows

📝 Other Changes

• Updated @vscode/vsce to latest version in package.json
• Added NuGet.config for signing package restoration
• Updated localization files with new entries
• Disabled automatic tag-triggered stable releases (now manual via publishExtension parameter)

Pipeline Flow

Build Stage                          Publish Stage
┌─────────────────────┐             ┌─────────────────────┐
│ Build Jobs (matrix) │             │     Sign Job        │
│ ├── linux-x64       │ artifacts   │ ├── Download all    │
│ ├── linux-arm64     │ ─────────►  │ ├── Sign all        │
│ ├── darwin-x64      │             │ └── Publish artifact│
│ ├── darwin-arm64    │             └─────────┬───────────┘
│ ├── win32-x64       │                       │
│ ├── win32-arm64     │             ┌─────────▼───────────┐
│ └── universal       │             │    Publish Job      │
└─────────────────────┘             │ ├── GitHub Release  │
                                    │ └── Marketplace     │
                                    └─────────────────────┘

Testing

• Verified nox --session install_bundled_libs works with pip-based downloads
• Pipeline tested with pre-release builds

Breaking Changes

Note: this break previous pipelines due to checking in loc files