Add blood decals, gore, mobile HUD, web start gate + touch/perf tests

Remove tools/fstest.html scratch page used to probe browser
fullscreen/orientation APIs.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EznnY8rH2dXhtono1kwsXg

tests/rigid_skin_test.gd

@@ -0,0 +1,93 @@
+extends SceneTree
+## Guard for the web/mobile rigid-skin conversion (rigid_skin.gd). The bug it protects against:
+## the converter used to key geometry by destination bone only, so every surface funnelled to a
+## bone collapsed onto one material — matadors came out bald with the wrong uniform colour on the
+## web build. It now keys per (bone, surface), so all source materials survive. This asserts the
+## matador keeps every distinct material after conversion, produces bone-attached pieces, and
+## hides the original skinned meshes (so they never hit the invisible-on-Mali skinning path).
+## Run: godot --headless --script res://tests/rigid_skin_test.gd
+
+const RigidSkin = preload("res://rigid_skin.gd")
+
+var _pass := 0
+var _fail := 0
+
+
+func _init() -> void:
+	_run.call_deferred()
+
+
+func _ok(c: bool, m: String) -> void:
+	if c:
+		_pass += 1
+		print("  PASS: ", m)
+	else:
+		_fail += 1
+		print("  FAIL: ", m)
+
+
+func _surface_mats(mi: MeshInstance3D) -> Array:
+	var out: Array = []
+	var mesh := mi.mesh
+	if mesh == null:
+		return out
+	for s: int in mesh.get_surface_count():
+		var mat: Material = mi.material_override
+		if mat == null:
+			mat = mi.get_surface_override_material(s)
+		if mat == null:
+			mat = mesh.surface_get_material(s)
+		if mat != null and not out.has(mat):
+			out.append(mat)
+	return out
+
+
+func _run() -> void:
+	var inst: Node = (load("res://Assets/Matador.glb") as PackedScene).instantiate()
+	root.add_child(inst)
+
+	# Distinct materials on the skinned source meshes, before conversion.
+	var source: Array = []
+	var skinned: Array = []
+	for mi: MeshInstance3D in inst.find_children("*", "MeshInstance3D", true, false):
+		if mi.skin != null:
+			skinned.append(mi)
+			for mat: Material in _surface_mats(mi):
+				if not source.has(mat):
+					source.append(mat)
+	_ok(source.size() >= 2, "matador source has multiple distinct materials (%d)" % source.size())
+
+	var converted := RigidSkin.convert_tree(inst)
+	_ok(converted > 0, "convert_tree rebuilt %d skinned mesh(es)" % converted)
+
+	# Distinct materials on the generated bone-attached pieces.
+	var pieces := 0
+	var piece_mats: Array = []
+	for att: BoneAttachment3D in inst.find_children("*", "BoneAttachment3D", true, false):
+		for mi: MeshInstance3D in att.find_children("*", "MeshInstance3D", true, false):
+			pieces += 1
+			var mesh := mi.mesh
+			if mesh == null:
+				continue
+			# Pieces are multi-surface now (a bone's materials each stay their own surface), so
+			# scan every surface — not just surface 0 — to confirm none were dropped.
+			for s: int in mesh.get_surface_count():
+				var mat := mesh.surface_get_material(s)
+				if mat != null and not piece_mats.has(mat):
+					piece_mats.append(mat)
+	_ok(pieces > 0, "conversion produced bone-attached pieces (%d)" % pieces)
+	_ok(piece_mats.size() >= source.size(),
+		"every source material survives conversion (%d of %d kept)" % [piece_mats.size(), source.size()])
+
+	var all_hidden := true
+	for mi: MeshInstance3D in skinned:
+		if mi.visible:
+			all_hidden = false
+	_ok(all_hidden, "original skinned meshes are hidden (never drawn on the failing path)")
+
+	_finish()
+
+
+func _finish() -> void:
+	print("Results: %d passed, %d failed" % [_pass, _fail])
+	quit(1 if _fail > 0 else 0)