[Rust/hotaru] Add Hotaru Rust framework

[JerrySu5379]

• Add Hotaru framework implementation for TechEmpower benchmarks
• Includes all 7 required benchmark tests (JSON, plaintext, db, queries, updates, fortunes, cached-queries)
• Performance: ~287K req/sec for plaintext and cached queries

All tests pass TechEmpower validation.

Framework Information

• Homepage: https://github.com/Field-of-Dreams-Studio/hotaru
• Documentation: https://docs.rs/hotaru
• Version: 0.7.7

Performance Results (512 concurrent connections)

• Plaintext: 286,871 req/sec
• Cached queries (1): 286,871 req/sec
• Cached queries (20): 191,350 req/sec
• Cached queries (100): 89,345 req/sec
• Average latency: 2-6ms

Implementation Details

• Uses Rust edition 2024
• All dependencies from crates.io
• In-memory caching with moka (10,000 entry capacity)
• Cache pre-warmed at startup
• PostgreSQL connection pooling with deadpool
• Akari template engine for HTML rendering