chore: modernize Processory for .NET 10

[myinusa]

Summary

• Target all projects at .NET 10 and pin SDK 10.0.301.
• Refresh runtime, test, coverage, and analyzer packages.
• Mark tests that require a running Football Manager process as integration-dependent skips.

Validation

• dotnet build Processory.sln --no-restore — passed with 0 errors and 16 existing analyzer warnings.
• dotnet test Processory.Tests/Processory.Tests.csproj --no-build --no-restore — passed; Football Manager-dependent tests skipped.
• dotnet list Processory.sln package --vulnerable --include-transitive — no vulnerable packages.

[myinusa]

Change chronology

1. Reviewed README.md, CHANGELOG.md, and docs/tips.md to confirm the library intent and historical framework changes before defining commit scope.
2. Upgraded the three projects from .NET 8 to .NET 10, pinned SDK 10.0.301, and refreshed runtime, testing, coverage, and analyzer dependencies.
3. Built the solution and resolved the test-suite portability issue by marking checks that require a live Football Manager process as explicit skips instead of allowing environment-dependent failures.
4. Re-ran the solution build, tests, and transitive vulnerability scan. The build completes with no errors, the external-process tests are skipped as intended, and NuGet reports no vulnerable packages.

The changes were split into a framework/dependency commit and a test-behavior commit so each concern can be reviewed independently.