[RejectKid]

Adds net11.0 to the library, unit tests, packed-package consumer, and benchmark harness while retaining .NET 8, 9, and 10. The NuGet package now includes a .NET 11 assembly, with CI and release workflows testing and validating all four targets.

Updates dependency lockfiles, framework documentation, and SDK setup in all affected workflows. BenchmarkDotNet moves to 0.16.0-preview.2 because stable 0.15.8 does not recognize .NET 11; this is a development-only dependency. Generated .bdn files are ignored.

Validation on Windows with SDK 11.0.100:

• Locked restore and Release build passed with zero warnings or errors.
• All 320 unit tests passed on each of .NET 8, 9, 10, and 11 (1,280 total).
• Package creation, compatibility validation, package inspection, and packed-package consumer smoke tests passed on all four runtimes.
• Formatting, generated-source verification, and fuzz smoke corpus passed.
• BenchmarkDotNet Dry smoke passed for typed Signal deserialization across three payload sizes and all four runtimes (12 cases). The benchmark host ran on .NET 10 with the .NET 11 CLI explicitly selected after the portable host encountered local file-access errors; full benchmark coverage remains in CI.