feat(*): Add self-play RL training pipeline with PPO trainer, in-game GDScript policy inference, and bot opponent support in Match mode

Game/addons/godot_rl_agents/onnx/wrapper/ONNX_wrapper.gd

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+extends Resource
+class_name ONNXModel
+var inferencer_script = load("res://addons/godot_rl_agents/onnx/csharp/ONNXInference.cs")
+
+var inferencer = null
+
+## How many action values the model outputs
+var action_output_size: int
+
+## Used to differentiate models
+## that only output continuous action mean (e.g. sb3, cleanrl export)
+## versus models that output mean and logstd (e.g. rllib export)
+var action_means_only: bool
+
+## Whether action_means_value has been set already for this model
+var action_means_only_set: bool
+
+# Must provide the path to the model and the batch size
+func _init(model_path, batch_size):
+	inferencer = inferencer_script.new()
+	action_output_size = inferencer.Initialize(model_path, batch_size)
+
+# This function is the one that will be called from the game,
+# requires the observations as an Dictionary and the state_ins as an int
+# returns a Dictionary containing the action the model takes.
+func run_inference(obs: Dictionary, state_ins: int) -> Dictionary:
+	if inferencer == null:
+		printerr("Inferencer not initialized")
+		return {}
+	return inferencer.RunInference(obs, state_ins)
+
+
+func _notification(what):
+	if what == NOTIFICATION_PREDELETE:
+		inferencer.FreeDisposables()
+		inferencer.free()
+
+# Check whether agent uses a continuous actions model with only action means or not
+func set_action_means_only(agent_action_space):
+	action_means_only_set = true
+	var continuous_only: bool = true
+	var continuous_actions: int
+	for action in agent_action_space:
+		if not agent_action_space[action]["action_type"] == "continuous":
+			continuous_only = false
+			break
+		else:
+			continuous_actions += agent_action_space[action]["size"]
+	if continuous_only:
+		if continuous_actions == action_output_size:
+			action_means_only = true

Game/addons/godot_rl_agents/onnx/wrapper/ONNX_wrapper.gd.uid

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+uid://c35ckkxpe764s