7.1.8-beta.1

Pre-release for #216 — media type (content type) & file size validation for IFormFile uploads. Tracks PR #218.

New File-level FluentValidation rules (MicroElements.OpenApi.FluentValidation.FileUpload):

RuleFor(x => x.File)
    .NotNull()
    .FileContentType("image/jpeg", "image/png")
    .MaxFileSize(2 * 1024 * 1024);

Also: .MinFileSize(long), .FileSizeBetween(long, long). They enforce at runtime and drive OpenAPI.

Backend	content type + size in description	encoding.contentType
Swashbuckle	✅	✅ (net8/9 = OAS 3.0; net10 = OAS 3.1)
NSwag	✅	✅ via FluentValidationOperationProcessor (encodingType — NSwag limitation)
Microsoft.AspNetCore.OpenApi	✅	❌ not emitted

Additive / opt-in — no existing document output changes. See CHANGELOG and PR #218.

Pre-release built from branch feature/issue-216-media-types (not yet merged to master).