Feature Request: Implement `threading` library.

[RadiantUwU]

Is your feature request related to a problem? Please describe. Sometimes, one thread isn't enough, and you'd require more than one thread inside Lua. There is a huge limitation around how Lua's states are not thread-safe.

Describe the solution you'd like A clear and concise description of what you want to happen. I would like a threading library that allows the following:

• Creating new threads, them creating their own LuaAPI state.
• Creating shared tables
• Creating synchronization primitives, such as semaphores, condition variables, and mutexes.
• Creating ContextedLuaFunctions, queues or blocks the LuaAPI calling this function to run a function on the thread that created this.
  • This allows using upvalues by reference since it remains under the same LuaAPI state.
• Passing values between threads, this includes mostly tables, Godot objects, Lua functions (cloning via lua_dump and lua_load, fails if upvalues are unable to be passed by value), C functions, ContextedLuaFunctions, synchronization primitives, etc. Describe alternatives you've considered Using multiple LuaAPI states and using RefCounteds for multi-threading.

Additional context Add any other context or screenshots about the feature request here. I can open a pull request for this feature request if need be.

[KevBruner]

Lua is not thread safe, and cannot be made thread safe in a reasonable way. Suggest closing this request.

[RadiantUwU]

Lua is not thread safe, and cannot be made thread safe in a reasonable way. Suggest closing this request.

Did you not read my... feature request...?