Add(test): chat validation

tests/chat_validation.gd

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+extends SceneTree
+
+const MainScene: PackedScene = preload("res://main/main.tscn")
+
+func _initialize() -> void:
+	call_deferred("_run")
+
+func _run() -> void:
+	## Regular whitespace should be stripped
+	assert(NetworkChatProtocol.sanitize_body("   a") == "a", "Leading space not trimmed")
+	assert(NetworkChatProtocol.sanitize_body("b   ") == "b", "Trailing space not trimmed")
+	assert(NetworkChatProtocol.sanitize_body("a b") == "a b", "Innocent whitespace culled")
+
+	## Some examples of Unicode whitespace that should be stripped
+	const em_space := " " # U+2003 EM SPACE
+	assert(NetworkChatProtocol.sanitize_body(em_space + "a") == "a")
+	const braille_space := "⠀" # U+2800 BRAILLE PATTERN BLANK
+	assert(NetworkChatProtocol.sanitize_body(braille_space + "a") == "a")
+
+	print("Chat validation: PASS")
+	quit(0)

tests/chat_validation.gd.uid

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+uid://ohemhv2sf5g4