[WIP] AutoShell Refactoring

[TalZaccai]

Structural refactoring of autoShell to make the codebase testable, maintainable, and extensible. No behavior changes — all 78 commands continue to work identically.

Phase 1: Structural Refactoring (Make It Testable)

• Extract OS abstraction interfaces (IAudioService, IRegistryService, ISystemParametersService, IProcessService)
• Extract 9 command handler classes by domain (AudioCommandHandler, WindowCommandHandler, SettingsCommandHandler, etc.)
• Replace 78-case execLine switch with CommandDispatcher + dictionary lookup
• Add missing error handling (centralized try/catch in dispatcher)
• Remove quit from handler return type — dispatcher handles it directly
• Add XML doc comments to all interface methods + <inheritdoc/> on implementations
• Clean up unused using directives across all files
• Add explicit private modifiers (satisfying .editorconfig rules)
• Unify all command names to PascalCase (C# handlers + TS schemas + connector)
• Run dotnet format for code style consistency

Phase 2: Unit Tests

• Create autoShell.Tests xUnit project with Moq
• Test command dispatch (verify correct handler for each action)
• Test AudioCommandHandler with mocked IAudioService (18 tests)
• Test settings handlers with mocked IRegistryService / ISystemParametersService (14 test classes)
• Test AppCommandHandler, ThemeCommandHandler, SystemCommandHandler with mocked services
• Test parameter parsing edge cases (covered by handler tests)
• Add reflection-based coverage test enforcing every command has at least one unit test
• Add dotnet test to CI

Phase 3: Deep Refactoring

• Split SettingsCommandHandler into 9 domain sub-handlers (Taskbar, Display, Mouse, Accessibility, Privacy, Power, FileExplorer, Personalization, SystemSettings)
• Extract shared app data into IAppRegistry service (replaces static fields)
• Migrate all scenario-specific logic from AutoShell.cs into handlers (~1429 → ~152 lines)
• Move all P/Invoke declarations into their respective domain handlers
• Move all COM interop (Virtual Desktop, Network) into respective handlers
• Add cross-handler helpers (WindowCommandHandler.RaiseWindow, FindProcessWindowHandle)
• Delete AutoShell_Win32.cs — all declarations now live in handlers
• Improve logging (replace Debug.WriteLine with proper abstraction)
• Enforce code style with dotnet format CI check
• Fix all build warnings (CA1806, SYSLIB1054) — target zero warnings