Improves the PR reviewer agent with Go-specific pattern detection, a multi-agent architecture, and dynamic feedback learning

[derekmisler]

• Multi-agent architecture: Root orchestrator delegates to drafter (generates bug hypotheses) and verifier (filters false positives)
• Go-specific detection: Drafter includes detailed patterns for error handling, concurrency, context usage, resource management, and common anti-patterns
• Feedback learning: New pr-review-feedback.yaml agent stores corrections from developer replies in a persistent memory DB
• Read-only filesystem: All agents restricted to read_file, read_multiple_files, list_directory, directory_tree

[Pnkcaht]

Hi @derekmisler I see that this PR seems complementary to what I did in #1472 about agent orchestration.
Depending on how the files have evolved, we can align to ensure everything works well together :)