Feat/hardening

[bxvtr]

Summary

Cleaned up and hardened tradingchassis_core as a standalone deterministic Core package. The Core Pipeline, public API, docs, examples, tests, and dead-code surface were aligned around the clean CoreStep/CoreWakeupStep architecture.

Motivation

This change makes Core easier to understand, use, test, and maintain as an independent trading decision engine. It removes legacy/unused surfaces, clarifies extension points, and strengthens confidence that Core remains deterministic and Runtime-independent.

Type of Change

• Bug fix
• New feature
• Performance improvement
• Refactor
• Documentation
• Breaking change

Technical Details

• Established the clean Core Pipeline: canonical events → reduction → Strategy Evaluator → candidate records → Policy Admission → Execution Control → CoreStepResult.
• Updated run_core_wakeup_step to reduce all entries first and evaluate strategy once on the final wakeup state.
• Added/clarified public extension points such as PolicyIntentEvaluator, RiskEngine, and ExecutionControl.
• Added Risk Engine and FillEvent coverage.
• Removed confirmed-dead code and narrowed public exports.
• Updated README, docs, examples, and changelog to match the clean Core package model.

Determinism & Reproducibility

• Change preserves deterministic behavior
• Tests confirm reproducibility
• No hidden state introduced

Performance Impact

• No measurable impact
• Benchmarks included
• Performance improvement

Tests

• Unit tests added/updated
• Integration tests added/updated
• Existing tests pass

Breaking Changes

Legacy compatibility APIs and unused public exports were removed or narrowed. Consumers relying on removed GateDecision-style or dead-code surfaces must migrate to the clean CoreStep/CoreWakeupStep API and CoreStepResult outputs.

Checklist

• Code follows project style guidelines
• Self-review completed
• Documentation updated (if needed)