Add support to export logs directly via OTLP

### Description

Whilst we can't support all of the variants suggested below, we should be able to support:
```cs
.WithLogging(logging =>logging.AddSentryExporter())
```

Sentry already [documents an OTLP endpoint for logs](https://docs.sentry.io/concepts/otlp/direct/logs/) so with a bit of fiddling we should be able to build an extension method that would work with the OTEL logging builder.

[Original feedback](https://github.com/getsentry/sentry-dotnet/issues/5350#issuecomment-4901465105) from @yasmoradi:

```cs
services.AddLogging(loggingBuilder =>
{
loggingBuilder.ConfigureLoggers(configuration);

loggingBuilder.AddOpenTelemetry(options =>
{
options.IncludeScopes = true;
options.IncludeFormattedMessage = true;
configuration.Bind("Logging:OpenTelemetry", options);
});
});

var openTelemetry = services.AddOpenTelemetry()
.WithMetrics(metrics =>
{
metrics.AddConsoleExporter(); // Console
metrics.AddSentryExporter(); // ⚠️Not supported
})
.WithTracing(tracing=>
{
tracing.AddConsoleExporter(); // Console
tracing.AddSentryExporter(); // ✅Supported
)
.WithLogging(logging =>
{
logging.AddConsoleExporter(); // Console
logging.AddSentryExporter(); //⚠️Not supported
})
.ConfigureResource(resource =>
{
resource.AddAttributes([new("service.name", Application.ProductName!)]);
});

openTelemetry.UseOtlpExporter(); // Aspire Dashboard

openTelemetry.UseAzureMonitorExporter(); // Azure Application Insights

openTelemetry.UseSentryExporter(); //⚠️ Not supported
```

Also worth considering the extensions on the `OpenTelemetryBuilder` in that case - these are likely/potentially shortcuts for adding exporters to logging and tracing in a single method call.

> [!NOTE]
> At thist stage, we don't export Sentry metrics to OTEL - that would be blocked by:
> - https://github.com/getsentry/sentry/issues/111136

Start by reading the existing AddSentryExporter support for OpenTelemetry tracing and the OpenTelemetry logging builder entry point. Determine how the Sentry OTLP logs endpoint should integrate with logging.AddSentryExporter() and the OpenTelemetryBuilder extensions. Done means the logging exporter works with the documented builder usage and is covered by the project's relevant tests.

Written by the indexing model from the issue text.