New features: Logging, Config, Generic Host, and documentation

Added

• Public CommandAppBuilder.Registrar getter and CommandAppBuilder.GetServiceCollection() helper so add-on extension packages can access the builder's DI container.
• Verbosity-aware logging that renders through Spectre.Console. New public API includes LoggingCommandAppBuilderExtensions.WithLogging, SpectreLoggingExtensions.AddSpectreConsole, SpectreConsoleLoggerProvider, SpectreConsoleLogger, SpectreConsoleLoggerOptions, and the VerbosityLevel/LogLevel mapping extensions.
• New Logging.Cli sample that demonstrates enabling verbosity-aware logging with WithLogging and injecting ILogger<T> into a command.
• New D20Tek.Spectre.Console.Extensions.Configuration package that adds Microsoft.Extensions.Configuration and Options binding to the builder. New public API includes ConfigurationCommandAppBuilderExtensions.WithConfiguration and ConfigurationCommandAppBuilderExtensions.WithOptions<TOptions>.
• New Configuration.Cli sample that demonstrates binding configuration with WithConfiguration and injecting IOptions<T> bound via WithOptions<TOptions> into a command.
• New D20Tek.Spectre.Console.Extensions.Hosting package that bridges Spectre.Console.Cli to the .NET Generic Host (Microsoft.Extensions.Hosting). New public API includes HostCommandAppExtensions.RunCommandAppAsync, HostCommandAppExtensions.RunCommandApp, HostCommandAppExtensions.CreateCommandApp, HostCommandAppExtensions.CreateCommandAppBuilder, and the HostCommandAppBuilder fluent builder. Run-time registrations captured from Spectre resolve through a composite provider, so a Spectre-registered type can depend on another Spectre-registered type while host services still take precedence.
• New HostStartupBase and HostStartupExtensions.WithStartup<TStartup> in the Hosting package, providing a host-aware startup that splits ConfigureServices (run pre-build against the host's IServiceCollection) from ConfigureCommands (applied post-build when the CommandApp is built).
• New GenericHost.Cli sample that demonstrates bridging Spectre.Console.Cli to the .NET Generic Host so command types resolve from the host's service provider.
• New docs/ documentation site with a flat structure: an introduction, a detailed getting-started guide, targeted guide-*.md task guides, and an api-reference.md hub with per-topic and per-package api-reference-*.md references covering the core, Configuration, Hosting, and MoreContainers packages.

Changed

• Upgraded Spectre dependencies to latest version 0.57.2.
• Updated other dependencies to latest versions.
• LoggingCommandAppBuilderExtensions.WithLogging now uses the new GetServiceCollection() accessor instead of reaching through the internal registrar.
• SpectreLoggingExtensions.AddSpectreConsole now sets the logging builder's minimum level from the mapped verbosity, so Debug and Trace entries are emitted when a more detailed verbosity is requested.
• The Configuration and MoreContainers packages now ship dedicated, package-specific README files (packed as the NuGet package readme) instead of the root repository README.
• Enabled SourceLink, symbol packages (snupkg), deterministic builds, and a shared package icon across all four NuGet packages, and consolidated shared package metadata and version into Directory.Build.props.

Fixed

• Corrected XML documentation on LamarTypeResolver, which previously referred to SimpleInjector instead of Lamar.
• Enabled XML documentation generation for the MoreContainers package and documented the previously undocumented public members so all four packages ship complete API docs.