Expose helper methods for converting UIDs

[KoBeWi]

Related #105414 (comment)

Exposes the static methods for converting between paths and UIDs. They are widely used in the engine and didn't change since they were added, so there is no reason to keep them unexposed. They make working with UIDs more convenient.

[Calinou]

Tested locally, it works as expected.

Testing project: test_pr_106717.zip

func _ready() -> void:
	print(ResourceUID.path_to_uid("res://node_2d.tscn"))
	print(ResourceUID.path_to_uid("res://node_2d.gd"))
	print(ResourceUID.path_to_uid("res://notfound"))
	print(ResourceUID.path_to_uid("not_res"))

	print()
	print(ResourceUID.uid_to_path("uid://bamx8gv7ycx3l"))
	print(ResourceUID.uid_to_path("uid://jdo0axvhs6by"))
	print(ResourceUID.path_to_uid("uid://notfound"))
	print(ResourceUID.path_to_uid("not_uid"))

	print()
	print(ResourceUID.ensure_path("res://node_2d.tscn"))
	print(ResourceUID.ensure_path("res://node_2d.gd"))
	print(ResourceUID.ensure_path("res://notfound"))
	print(ResourceUID.ensure_path("not_res"))

	print()
	print(ResourceUID.ensure_path("uid://bamx8gv7ycx3l"))
	print(ResourceUID.ensure_path("uid://jdo0axvhs6by"))
	print(ResourceUID.ensure_path("uid://notfound"))
	print(ResourceUID.ensure_path("not_uid"))

Outputs:

uid://bamx8gv7ycx3l
uid://jdo0axvhs6by
res://notfound
not_res

res://node_2d.tscn
res://node_2d.gd
uid://notfound
not_uid

res://node_2d.tscn
res://node_2d.gd
res://notfound
not_res

res://node_2d.tscn
res://node_2d.gd

not_uid

One interesting difference is that using ensure_path() with res://notfound returns the string as-is, while uid://notfound returns an empty string.

[Repiteo]

Thanks!