Add logging, response-language enforcement, and parallel Operator requests (v10.2.0)

[techbuzzz]

Pull Request

Description

Bumps Delibera to v10.2.0 with three features requested by NuGet consumers:

1. Microsoft.Extensions.Logging support — inject your own ILogger / ILoggerFactory and every debate event (Chairman opening, Knowledge Keeper queries, compression, Operator interactions, participant responses, errors) is forwarded to the host's logging pipeline, in addition to the in-memory ExecutionLog collection and the OnLog/OnError events.

   • New APIs: ICouncilBuilder.WithLogger(ILogger?), ICouncilExecutor.Logger, AddDelibera(services, IConfiguration, ILoggerFactory, string?).
   • ExecutionLog events flow to the logger via ExecutionLogSink.Emit(...) with a structured EventId(Source); errors use ILogger.LogError(ex, ...).
   • New DebateExecutionOptions record bundles the logger (plus response-language + parallelism) threaded through strategies via a new IDebateStrategyWithOptions interface (default method on IDebateStrategy keeps custom strategies working unchanged).

2. Performance — parallel Operator requests — [[OPERATOR: …]] tasks delegated by participants within a round now run concurrently via Parallel.ForEachAsync, bounded by MaxDegreeOfParallelism (0 = unbounded, default). All Delibera-shipped strategies (StandardDebate, CritiqueDebate, ConsensusDebate) opt in via the new ExecuteAsync(..., DebateExecutionOptions, ...) overload.

   • New APIs: ICouncilBuilder.WithMaxDegreeOfParallelism(int), CouncilOptions.MaxDegreeOfParallelism.

3. Response-language enforcement — force every model (participants, Chairman, Knowledge Keeper, Operator) to answer in a specific language, regardless of the prompt or retrieved RAG context. Delibera injects a strict directive into every system prompt: "You MUST answer exclusively in {language}. Never use any other language…".

   • New APIs: ICouncilBuilder.WithResponseLanguage(string?), CouncilOptions.ResponseLanguage.

Breaking change

• Renamed the LogLevel enum (in Delibera.Core.Models) to ExecutionLogLevel to avoid the name clash with Microsoft.Extensions.Logging.LogLevel, which is now referenced throughout the framework. Consumers that referenced LogLevel.Info etc. directly should switch to ExecutionLogLevel.Info. Added ExecutionLog.ToMicrosoftLogLevel() to bridge the two worlds. This is the only source-breaking change; the legacy IDebateStrategy.ExecuteAsync(...) overload is preserved via a default method so custom strategies keep working.

Configuration (appsettings.json)

{
  "Delibera": {
    "ResponseLanguage": "Russian",
    "MaxDegreeOfParallelism": 0
  }
}

README.md, src/Delibera.Core/README.md, and CHANGELOG.md are updated with full examples for each new feature. NuGet package metadata bumped to 10.2.0 with updated release notes.

Related Issues

N/A — requested directly by maintainers.

Type of Change

• 🐛 Bug fix (non-breaking change that fixes an issue)
• ✨ New feature (non-breaking change that adds functionality)
• 💥 Breaking change (fix or feature that changes existing behaviour)
• 📚 Documentation update
• 🧹 Refactor / chore

Checklist

• My code follows the project's coding standards (see CONTRIBUTING.md)
• The solution builds with 0 errors and 0 warnings (dotnet build --configuration Release)
• I have added/updated XML documentation for public APIs
• I have updated relevant documentation (README.md, QuickStart.md)
• I have tested my changes (examples run as expected)

Additional Notes

• Breaking change is limited to the enum rename (LogLevel → ExecutionLogLevel). All other additions are additive and backward compatible: the legacy IDebateStrategy.ExecuteAsync(...) overload delegates to the new one via a default interface method, so existing custom strategies continue to work without recompilation.
• The PR groups 7 commits that were already on develop; this is the cumulative diff from main to develop. Reviewers should focus on the latest commit (0e37696 Add logging, language enforcement, and parallel Operator) for the v10.2.0 changes.
• Verified: dotnet build --configuration Release → 0 errors, 0 warnings; dotnet test --configuration Release → 20/20 passed.

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