fix: RateLimiter factory and initialization race condition

[fr3on]

Description

Resolved memory leak and initialization race condition in the rate limiter registration.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• PHPStan reports no errors

[github-actions]

🚀 Quill Performance Metrics

Environment: Ubuntu · PHP 8.3 · quill-core 0.0.2 · 2 workers Quill Core

Quill Binary Benchmark
  > Server     : Quill Core
  > Tool       : wrk
  > Duration   : 5s
  > Connections: 50
  > Workers    : 2
  > Starting Quill server...
  > Server is ready. Running benchmarks...
    Running 5s test @ http://127.0.0.1:8080/hello
      2 threads and 50 connections
      Thread Stats   Avg      Stdev     Max   +/- Stdev
        Latency     1.01ms  383.19us  10.81ms   92.90%
        Req/Sec    25.01k     3.91k   28.12k    85.29%
      253672 requests in 5.10s, 39.19MB read
    Requests/sec:  49737.37
    Transfer/sec:      7.68MB

  > Benchmarks completed.