test: 八项无头回归测试（道具/弹道/Boss/海面/地面单位/浮游炮/炸弹/冒烟模拟）

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

tests/ocean_test.gd

@@ -0,0 +1,46 @@
+extends SceneTree
+## 海面覆盖回归测试：滚动两个完整周期（1200 帧），
+## 逐帧断言贴图联合覆盖包含整屏 Rect2(0,0,540,960)。
+## 运行：godot --headless -s tests/ocean_test.gd
+
+const SCREEN := Rect2(0.0, 0.0, 540.0, 960.0)
+const TILE_HALF := Vector2(270.0, 270.0)
+const FRAMES := 1200
+
+var _ocean: OceanScroll
+var _frames := 0
+var _fails := 0
+
+
+func _initialize() -> void:
+	_ocean = OceanScroll.new()
+	root.add_child(_ocean)
+	print("[ocean_test] ocean instantiated")
+
+
+func _process(_delta: float) -> bool:
+	_frames += 1
+	# 第 1 帧本回调先于海面节点的首个 _process，跳过（贴图尚未定位）
+	if _frames >= 2:
+		var covered := Rect2()
+		var first := true
+		for tile in _ocean._tiles:
+			var rect := Rect2(tile.position - TILE_HALF, TILE_HALF * 2.0)
+			if first:
+				covered = rect
+				first = false
+			else:
+				covered = covered.merge(rect)
+		if not covered.encloses(SCREEN):
+			_fails += 1
+			if _fails <= 3:
+				print("[FAIL] frame %d coverage=%s tiles=%s" % [_frames, covered, _ocean._tiles.map(func(t): return t.position)])
+
+	if _frames >= FRAMES:
+		if _fails == 0:
+			print("[ocean_test] PASS: %d 帧整屏全覆盖" % FRAMES)
+		else:
+			print("[ocean_test] FAIL: %d/%d 帧覆盖不足" % [_fails, FRAMES])
+		quit(1 if _fails > 0 else 0)
+		return true
+	return false