Frends.JSON.Query: fix compliance findings (net8, static class, CancellationToken, error handling)

[Copilot]

Resolves five task-analyzer findings (FT0004, FT0007, FT0011, FT0015 ×2) plus csproj compliance gaps in Frends.JSON.Query. Bumps target framework to net8 and version to 1.3.0.

csproj

• Frends.JSON.Query.csproj: net6.0 → net8.0, version 1.2.0 → 1.3.0
• Frends.JSON.Query.UnitTests.csproj: net6.0 → net8.0, added <PackageProjectUrl> and <Product>Frends</Product> (the UnitTests suffix is not matched by the *.Test*.csproj exclude pattern)

Definitions

• Options: added ThrowErrorOnFailure (bool, default true) and ErrorMessageOnFailure (string, default "") — FT0015
• Error (new): Message + AdditionalInfo (Exception)
• Result: added Error property; added internal constructor for the failure path — FT0011

Task class (Query.cs)

• JSON made static — FT0004
• Query gains a CancellationToken parameter — FT0007
• Method body wrapped in try/catch following the standard ErrorHandler pattern:
  • OperationCanceledException is always rethrown
  • Other exceptions: thrown (wrapped) when ThrowErrorOnFailure = true (default, preserves existing behaviour); returned as Result { Success=false, Error=… } when false

// New signature
public static Result Query(
    [PropertyTab] Input input,
    [PropertyTab] Options options,
    CancellationToken cancellationToken)

// Non-throwing path
var options = new Options { ThrowErrorOnFailure = false };
var result = JSON.Query(input, options, cancellationToken);
// result.Success == false, result.Error.Message populated

Tests

• Existing calls updated with CancellationToken.None
• QueryShouldThrowIfOptionSetAndFilterMatchesNothing updated to assert Exception (error handler wraps the original JsonException)
• Added QueryShouldReturnErrorResultWhenThrowErrorOnFailureIsFalse

[MichalFrends1]

@copliot instead of this test please create new error handler class same like this one: https://github.com/FrendsPlatform/Frends.Smb/blob/main/Frends.Smb.WriteFile/Frends.Smb.WriteFile.Tests/ErrorHandlerTest.cs

[MatteoDelOmbra]

use nunit for new tests

[Copilot]

Done — ErrorHandlerTests.cs now uses NUnit ([TestFixture]/[Test]/Assert.That). Added NUnit 4.3.2 and NUnit3TestAdapter 5.0.0 packages to the test csproj.

[MatteoDelOmbra]

remove this note, not important for a user

[Copilot]

Removed that line from the CHANGELOG.

[MatteoDelOmbra]

@copilot resolve review comments