refactor: optimize async finality&commit&atomic

[AshinGau]

Summary

• Replaces the legacy async-commit and static-hint paths with a coordinated pipeline for speculative execution, validation finality, and ordered commits.
• Publishes finality as a contiguous validated prefix, handles validation rewinds, and commits state, nonce updates, deferred beneficiary rewards, and outcomes in block order.
• Replays only the uncommitted suffix after nonce mismatches or recoverable scheduler aborts, while preserving the committed prefix on fatal errors.
• Refactors scheduler cursor, dependency, wait, fallback, metrics, and state/bundle handling; updates the public API and documentation; and adds focused concurrency and error-path tests.

Tests

• cargo fmt --all -- --check
• cargo test --lib