feat: support Alibaba Function Compute as sandbox runtime provider

[insight-bit]

Background

ROCK currently supports multiple deployment modes including Docker, Ray, and K8s. Adding Alibaba Cloud Function Compute (FC3) as a sandbox runtime provider would enable serverless deployment of ROCK sandboxes, reducing operational overhead and enabling auto-scaling.

Feature Request

Add comprehensive support for Alibaba Cloud Function Compute 3.0 (FC3) as a sandbox runtime provider with three deployment modes:

1. Custom Runtime: Lightweight Python runtime with bootstrap script
2. Custom Container: Full Docker container deployment
3. Hybrid Adapter: HTTP/WebSocket adapter for FC3 function integration

Key Components

FC3 Client

• FC3Sandbox: Main sandbox client with session management
• CircuitBreaker: Thread-safe fault tolerance with OPEN/CLOSED/HALF_OPEN states
• WebSocket reconnection with exponential backoff retry
• Custom exceptions for error handling

FC3 Rocklet

• runtime/: Custom Runtime bootstrap and configuration
• container/: Custom Container Dockerfile and configuration
• adapter/: Hybrid Adapter HTTP/WebSocket server with path traversal protection

Tests

• 126 test cases covering client, adapter, and runtime configurations

Benefits

• Serverless: No infrastructure management required
• Auto-scaling: Automatic scaling based on workload
• Cost-effective: Pay-per-use pricing model
• High availability: Built-in fault tolerance