Add hot reload functionality to Jac-Scale Server

[mgtm98]

Description

Implemented hot-reload by invoking a new process that actually calls jac-scal,e and the main process will watch the files. If a file has changed, then the invoked process will be terminated a new process will be created. Check the diagram below digaram

Parent Process (Watcher)          Child Process (Server)
┌──────────────────┐              ┌──────────────────┐
│ Watches .jac     │─────spawn────│ Runs uvicorn     │
│ files using      │              │ on port 8000     │
│ watchfiles       │              │                  │
└──────────────────┘              └──────────────────┘
        │                                  │
        │ File change detected!            │
        │                                  │
        ├──── process.terminate() ─────►  │
        │                                  │
        │      Wait 3 seconds...           │
        │                                  │
        │                                  ✗ Process exits
        │                                    Port 8000 released
        │
        ├──── Spawn new child ─────────►  
        │                              ┌──────────────────┐
        │                              │ Fresh Python     │
        │                              │ Fresh compilation│
        │                              │ Fresh endpoints  │
        │                              │ Binds port 8000  │
        │                              └──────────────────┘