Add SDK bootstrap and sdkmanager wrapper (move from android-platform-support)

[rmarinho]

Summary

Add SDK bootstrap and management capabilities to Xamarin.Android.Tools.AndroidSdk so that consumers can programmatically set up an Android SDK from scratch and manage packages via sdkmanager.

Background

The android-platform-support (internal) repository has AndroidSDKInstaller with a full SDK install pipeline. For the public package, we want a simpler approach:

1. Bootstrap: Download and unzip Android command-line tools from the manifest feed (no hardcoded URLs)
2. Manage: Use the extracted sdkmanager CLI for package install/uninstall/list/update operations

This is needed by MAUI DevTools CLI (maui android install, maui android sdk install/list/uninstall).

Proposed API Surface

• SdkManager.BootstrapAsync(targetPath) — download command-line tools from manifest feed, SHA-1 verify, unzip to cmdline-tools/latest/
• SdkManager.InstallAsync(packages) — invoke sdkmanager to install packages
• SdkManager.UninstallAsync(packages) — invoke sdkmanager to uninstall packages
• SdkManager.ListAsync() — list installed and available packages
• SdkManager.UpdateAsync() — update all installed packages

Bootstrap Flow

1. Read manifest feed → resolve command-line tools URL + SHA-1 checksum for current OS/arch
2. Download & verify command-line tools archive
3. Unzip to \/cmdline-tools/latest/
4. Use the now-available sdkmanager for all subsequent operations

Manifest Feeds

• Xamarin Android Manifest: https://aka.ms/AndroidManifestFeed/d{version} — command-line tools, platform-tools, emulator
• Google SDK Repository: https://dl.google.com/android/repository/repository2-3.xml — platforms, build-tools, system images

All downloads must be SHA-1 verified against manifest checksums before installation.

Consumer

• MAUI DevTools CLI — see MAUI DevTools Spec PR

Related

• MAUI DevTools spec §6.8: Shared Libraries & Code Reuse
• MAUI DevTools spec §6.8.1: Manifest-Driven Downloads & Checksum Verification

[rmarinho]

Implementation Progress

I've implemented partial support for this issue as part of MAUI DevTools work:

✅ Implemented: sdkmanager wrapper (SdkManagerRunner)

`csharp
public class SdkManagerRunner
{
// List installed and available packages
Task<IReadOnlyList> ListPackagesAsync(bool includeAll = false, CancellationToken ct = default);

// Install SDK packages
Task<ToolRunnerResult> InstallPackagesAsync(IEnumerable<string> packages, CancellationToken ct = default);

// Accept all pending licenses
Task<ToolRunnerResult> AcceptLicensesAsync(CancellationToken ct = default);

}
`

Location: src/Xamarin.Android.Tools.AndroidSdk/Runners/SdkManagerRunner.cs

❌ NOT Implemented: SDK Bootstrap

The bootstrap functionality (downloading cmdline-tools when no SDK exists) is not yet implemented because it depends on #273 (Manifest Feed Parsing).

Current implementation assumes cmdline-tools/latest/bin/sdkmanager already exists.

What's needed to complete this issue

1. Add manifest feed parsing for SDK/JDK download resolution (move from android-platform-support) #273 must be implemented first (manifest feed parsing)
2. Then add SdkManager.BootstrapAsync(targetPath):
   • Read manifest → resolve cmdline-tools URL for current OS/arch
   • Download archive
   • Verify SHA-1 checksum
   • Extract to <targetPath>/cmdline-tools/latest/

Related issues

• Add AVD Manager wrapper (avdmanager CLI) #277 (AVD Manager wrapper) - implemented
• Add ADB wrapper (adb CLI) #279 (ADB wrapper) - implemented
• Add Emulator runner (emulator CLI) #278 (Emulator runner) - implemented