Add asynchronous HTTP handling with HttpAsync module

[cocorico8]

Description

This PR introduces a comprehensive, non-blocking asynchronous networking suite to the server-side Lua API, consisting of the AsyncHttp and AsyncWebSocket modules. It provides modders with high-performance tools for external integrations while strictly protecting the server's main thread and system resources.

Key Features:

• Full REST & WebSocket Support: Implements GET, POST, PUT, PATCH, DELETE, HEAD, and full-duplex WebSockets (ws:// and wss://).
• Request Handles & Cancellation: All requests return a handle allowing for manual cancellation via :Cancel(), which immediately severs the underlying TCP socket to reclaim resources.
• Smart Payload Handling: Automatically detects Lua tables and encodes them to JSON, defaulting to application/json where appropriate.
• Advanced Networking:
  • Separate Timeouts: Granular control over Connection and Read timeouts to prevent thread-hangs on dead endpoints.
  • Standards Compliant Headers: Support for multi-value headers (e.g., multiple Set-Cookie fields) and automatic lowercase header normalization for easy Lua access.
• File I/O: Streaming Download to disk and PostFile for multipart form-data uploads.
• Universal Progress Tracking: Real-time progress callbacks supported for all HTTP methods and downloads.

Stability & Safety Implementation:

• Dynamic Resource Scaling: The module automatically scales the internal httplib::ThreadPool and WebSocket quotas based on the host's hardware (CPU thread count).
• Plugin Sandboxing: Implements per-plugin rate limiting (quotas) for both HTTP requests and active WebSocket threads. This prevents a single buggy or malicious script from exhausting the server's network capacity.
• Memory Management:
  • Utilizes a thread-safe result queue processed during the server's Update cycle to ensure Lua callbacks only execute on the main thread.
  • Robust CleanupState and Abandon logic ensures all Lua Registry references are freed and background threads are terminated immediately when a script reloads or stops.
• Thread Safety: Comprehensive use of mutexes and atomic booleans across the bridge to prevent race conditions during async operations.

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[cocorico8]

currently there's a bug in the version of cpp-httplib, I would need to update the baseline to get rid of it to avoid using hacky solution, should i make another pr to update the vcpkg baseline (tried in a debian 12 vm that it still compiles and it does)