refactor: standardize project structure and verification

[YishenTu]

Summary

• reorganize production and test sources by domain and standardize Swift naming
• add swift-format linting, focused development scripts, and shared arm64 verification settings
• add vendored resource integrity checks and align CI with the new paths and tooling
• remove the obsolete docs directory

Verification

• ./scripts/verify.sh
• Debug and Release builds
• 366 non-performance tests
• 10 Benchmark tests
• architecture fixtures, Swift lint, and vendored resource checks