chore: clean up examples, update ML binaries and risk tests

- Delete 14 unused example files (-3,543 lines): config, adaptive-strategy,
  data, storage, trading_engine, api_gateway, backtesting, trading_service, chaos
- Update ML training/eval binaries: improved CLI args, completion tracking,
  CUDA test cleanup, hyperopt enhancements
- Fix KAN network and TFT module adjustments
- Update risk test assertions for consistency
- Fix backtesting repositories and promotion manager
- Update .serena project config and Cargo dependencies

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

services/backtesting_service/src/repositories.rs

@@ -120,7 +120,7 @@ impl BacktestingRepositories for DefaultRepositories {
     }
 }
 
-#[cfg(test)]
+#[cfg(any(test, feature = "test-utils"))]
 impl DefaultRepositories {
     /// Create a mock instance for testing
     ///