Add Icon property to McpManifestServer. Add Options and OptionsFrom properties to McpManifestConfig for static and dynamic value lists. Add McpManifestOptionsFrom class with File and Path properties for JSONPath-based option resolution
Create McpManifest NuGet package with autodiscovery and validation:
- McpManifestDiscovery: resolve manifests from domains/URLs/files
- McpManifestValidator: schema and semantic validation
- Models/McpManifest: strongly-typed manifest model classes
- Supports .NET 8.0, 9.0, and 10.0
- Implements full autodiscovery protocol (well-known URL + HTML link tags)
- Validates config keys, template variables, and transport consistency
- Async/await with cancellation token support
- Published as McpManifest package to NuGet
