SG-40699 Issue a deprecation warning for using engine::init_engine

[julien-lang]

No description provided.

[Copilot]

Pull Request Overview

This PR adds a deprecation warning for the init_engine method in the Engine class to notify users that it will be removed in future versions and should be replaced with pre_app_init.

• Adds a deprecation warning that triggers when init_engine method is accessed
• Implements the warning using __getattribute__ method override to intercept attribute access

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[Copilot]

The __getattribute__ method is called for every attribute access on Engine instances, which could impact performance. Consider using a decorator on the init_engine method itself or checking if the attribute exists before issuing the warning to avoid unnecessary overhead for non-existent attributes.

Suggested change

	def __getattribute__(self, attr):
	if attr == "init_engine":
	warnings.warn(
	f"The method Engine.init_engine is deprecated and will be removed in future versions. "
	f"Please use pre_app_init instead.",
	DeprecationWarning,
	)
	return super().__getattribute__(attr)
	# Removed __getattribute__ override. Deprecation warning will be added to init_engine.