[P-01] Breaking-Change Cleanup — remove [Obsolete], consolidate API, unify strategy signatures

[techbuzzz]

Overview

Version: v10.3.0 Platform Release
Effort: S · 1–2 days
Branch: feature/p01-breaking-change-cleanup

Clean up all deferred breaking changes accumulated since v10.1 to prepare a stable, clean public API surface for the 10.3.0 GA NuGet release.

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Tasks

1. Remove all [Obsolete] members

• Scan entire Delibera.Core for [Obsolete] attributes
• Delete all obsolete members (methods, constructors, properties)
• Verify no internal code references removed members
• Update XML doc comments on replacements if needed

2. Consolidate CouncilBuilder method overloads

• Audit all overloads, identify redundant ones
• Reduce API surface — prefer optional parameters over N overloads
• Ensure all removed overloads have a direct equivalent in the consolidated API

3. ILLMProvider.GetModelCapabilitiesAsync — make non-optional

• Remove default null return from the interface
• Force all provider implementations to return a real ModelCapabilities object
• Update OllamaProvider, OpenAiProvider, AzureOpenAiProvider, AnthropicProvider, ChatClientLLMProvider

4. Unify IDebateStrategy.ExecuteAsync signatures

• Remove IDebateStrategyWithOptions shim interface
• Merge options into IDebateStrategy.ExecuteAsync directly
• Update StandardDebate, CritiqueDebate, ConsensusDebate, AdaptiveStrategySelector

5. Rename RagProviderFactory → VectorStoreFactory

• Rename class and all references
• Add [Obsolete] type alias for one version if needed during transition
• Update usages in CouncilBuilder, KnowledgeKeeper, Delibera.Server templates

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Acceptance Criteria

• Zero [Obsolete] attributes remain in Delibera.Core
• ILLMProvider.GetModelCapabilitiesAsync has no default implementation — all providers implement it
• IDebateStrategyWithOptions shim removed
• RagProviderFactory renamed to VectorStoreFactory everywhere
• dotnet build — 0 errors, 0 warnings across all projects
• CHANGELOG.md entry with full breaking-change migration guide
• README.md + README-RU.md updated for renamed APIs

Labels

breaking-change, cleanup, v10.3.0