Replace Event + GlobalAnimation autoloads with class_name + static funcs

Two of the five autoloads were stateless helper bundles, not the
persistent application-wide systems that the Godot 4 best-practice
guide reserves autoload slots for. Convert them to plain classes with
all-static methods so they no longer need a Node living under /root.

- scripts/Animation.gd -> scripts/game_animation.gd (renamed:
  conflict with the built-in Animation class; the autoload sidestepped
  it by being called GlobalAnimation). class_name GameAnimation,
  every helper static. The dissolve tween now captures its target
  material in a lambda closure, eliminating the current_material
  member that the autoload kept as shared mutable state.
- scripts/Event.gd -> scripts/event.gd, class_name Event, every
  handler static. Added Event.level_pressed(name) -> Callable for the
  one place ChooseScene needed dynamic lookup of a per-level handler
  (replaces the old _build_method('_on_' + name + '_pressed') +
  Callable(autoload, string) reflection trick with an explicit match).

Updated call sites:
- scripts/Global.gd: animation.connect('animation_started',
  Callable(Event, '...')) -> animation.animation_started.connect(
  Event._loading_is_started). Same for animation_finished.
- scenes/levels/Levels.gd: GlobalAnimation.* -> GameAnimation.*;
  Quit/TextureButton.connect('pressed', Callable(Event, '...')) ->
  pressed.connect(Event._on_main_scene_pressed).
- scenes/UI/choose_scenes/ChooseScene.gd: per-level button connects
  go through Event.level_pressed(); reset button's bound callable now
  reads Event._on_reset_level.bind(...); cleanup no longer relies on
  is_connected with an unbound Callable (which would never match a
  bound one anyway) -- iterates reset.pressed.get_connections()
  instead. Drop the now-dead _build_method helper.

Also: organise scripts/ by promoting the one-shot migration helpers
(migrate_shaders, migrate_misc, resave_scenes, devisualize_shaders,
find_visualshaders) into scripts/migration/. They are not part of
the runtime and should not be browsable next to the autoloads.

Autoload count goes 5 -> 3 (Loading, Global, Setting remain --
Setting will move to a Resource in a later refactor).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

scripts/migration/devisualize_shaders.gd

@@ -0,0 +1,57 @@
+@tool
+extends SceneTree
+
+# Replace every VisualShader in the project with a plain Shader carrying the
+# same compiled code. Godot 4 spams "graph_offset deprecated" and "p_from_port
+# out of bounds" warnings every time it reconstructs a Godot-3 VisualShader
+# graph; converting to plain Shader bypasses the graph reconstruction entirely.
+
+func _init() -> void:
+	var fixed := 0
+	for path in _walk("res://"):
+		if not (path.ends_with(".material") or path.ends_with(".tres") or path.ends_with(".mesh")):
+			continue
+		var res = ResourceLoader.load(path, "", ResourceLoader.CACHE_MODE_IGNORE)
+		if res == null:
+			continue
+		var dirty := false
+		if res is ShaderMaterial and res.shader is VisualShader:
+			res.shader = _to_plain(res.shader)
+			dirty = true
+		if res is ArrayMesh:
+			for i in range(res.get_surface_count()):
+				var m = res.surface_get_material(i)
+				if m is ShaderMaterial and m.shader is VisualShader:
+					m.shader = _to_plain(m.shader)
+					res.surface_set_material(i, m)
+					dirty = true
+		if dirty:
+			if ResourceSaver.save(res, path) == OK:
+				fixed += 1
+				print("FIXED ", path)
+			else:
+				push_error("Failed to save " + path)
+	print("Done. fixed=", fixed)
+	quit()
+
+func _to_plain(vs: VisualShader) -> Shader:
+	var plain := Shader.new()
+	plain.code = vs.code
+	return plain
+
+func _walk(p: String) -> Array:
+	var out := []
+	var d = DirAccess.open(p)
+	if d == null: return out
+	d.list_dir_begin()
+	var n = d.get_next()
+	while n != "":
+		if n != "." and n != ".." and n != "android" and not n.begins_with("."):
+			var sub = p if p.ends_with("/") else (p + "/")
+			sub += n
+			if d.current_is_dir():
+				out.append_array(_walk(sub))
+			else:
+				out.append(sub)
+		n = d.get_next()
+	return out

scripts/migration/devisualize_shaders.gd.uid

@@ -0,0 +1 @@
+uid://cr456dqaoxcfh

scripts/migration/find_visualshaders.gd

@@ -0,0 +1,39 @@
+@tool
+extends SceneTree
+
+func _init() -> void:
+	for path in _walk("res://"):
+		if path.ends_with(".material") or path.ends_with(".tres") or path.ends_with(".mesh"):
+			var res = ResourceLoader.load(path, "", ResourceLoader.CACHE_MODE_IGNORE)
+			_check(res, path)
+	quit()
+
+func _check(res, path: String) -> void:
+	if res == null: return
+	if res is ShaderMaterial:
+		if res.shader is VisualShader:
+			print("VS: ", path)
+		elif res.shader is Shader:
+			pass
+	if res is ArrayMesh:
+		for i in range(res.get_surface_count()):
+			var m = res.surface_get_material(i)
+			if m is ShaderMaterial and m.shader is VisualShader:
+				print("VS-embed: ", path, " surf=", i)
+
+func _walk(p: String) -> Array:
+	var out := []
+	var d = DirAccess.open(p)
+	if d == null: return out
+	d.list_dir_begin()
+	var n = d.get_next()
+	while n != "":
+		if n != "." and n != ".." and n != "android" and not n.begins_with("."):
+			var sub = p if p.ends_with("/") else (p + "/")
+			sub += n
+			if d.current_is_dir():
+				out.append_array(_walk(sub))
+			else:
+				out.append(sub)
+		n = d.get_next()
+	return out

scripts/migration/find_visualshaders.gd.uid

@@ -0,0 +1 @@
+uid://br08uppmwhvjg

scripts/migration/migrate_misc.gd

@@ -0,0 +1,52 @@
+@tool
+extends SceneTree
+
+# One-shot cleanup:
+#  1. Reset VisualShader.graph_offset to default on every .material so the
+#     deprecated property no longer triggers a warning at load.
+#  2. Re-save every .mesh whose surface format is the old (Godot 3) variant
+#     so Godot 4 stops nagging.
+
+func _init() -> void:
+	var changed := 0
+
+	for path in _find_resources("res://assets", [".material", ".tres"]):
+		var res = ResourceLoader.load(path, "", ResourceLoader.CACHE_MODE_IGNORE)
+		if res is ShaderMaterial and res.shader is VisualShader:
+			var vs: VisualShader = res.shader
+			if vs.graph_offset != Vector2.ZERO:
+				vs.graph_offset = Vector2.ZERO
+				if ResourceSaver.save(res, path) == OK:
+					changed += 1
+					print("CLEARED graph_offset on ", path)
+
+	for path in _find_resources("res://assets", [".mesh"]):
+		var mesh = ResourceLoader.load(path, "", ResourceLoader.CACHE_MODE_IGNORE)
+		if mesh is ArrayMesh:
+			# Just re-saving rewrites the file using the current surface format.
+			if ResourceSaver.save(mesh, path) == OK:
+				changed += 1
+				print("RESAVED mesh ", path)
+
+	print("Done. changed=", changed)
+	quit()
+
+func _find_resources(dir_path: String, exts: Array) -> Array:
+	var result := []
+	var dir = DirAccess.open(dir_path)
+	if dir == null:
+		return result
+	dir.list_dir_begin()
+	var name = dir.get_next()
+	while name != "":
+		if name != "." and name != "..":
+			var sub = dir_path + "/" + name
+			if dir.current_is_dir():
+				result.append_array(_find_resources(sub, exts))
+			else:
+				for ext in exts:
+					if name.ends_with(ext):
+						result.append(sub)
+						break
+		name = dir.get_next()
+	return result

scripts/migration/migrate_misc.gd.uid

@@ -0,0 +1 @@
+uid://be5t0j47tufka

scripts/migration/migrate_shaders.gd

@@ -0,0 +1,85 @@
+@tool
+extends SceneTree
+
+# One-shot migration tool: walk every resource that can carry a ShaderMaterial
+# (.material, .tres, .mesh, .scn, .gltf, .glb, .tscn) and fix Godot 3 -> 4
+# shader code in-place, saving where possible.
+#
+# Run with: godot --headless --script scripts/migrate_shaders.gd
+
+const REPLACEMENTS := [
+	["depth_draw_alpha_prepass", "depth_prepass_alpha"],
+	["hint_color", "source_color"],
+	["hint_albedo", "source_color"],
+	["hint_black_albedo", "source_color"],
+	["hint_white", ""],
+	["hint_black", ""],
+	["hint_aniso", "hint_anisotropy"],
+	["NORMALMAP", "NORMAL_MAP"],
+]
+
+const EXTENSIONS := [".material", ".tres", ".mesh"]
+
+func _init() -> void:
+	var fixed := 0
+	var checked := 0
+	for path in _find_resources("res://assets"):
+		checked += 1
+		var res = ResourceLoader.load(path, "", ResourceLoader.CACHE_MODE_IGNORE)
+		if res == null:
+			continue
+		var dirty := false
+		# Direct ShaderMaterial
+		if res is ShaderMaterial:
+			dirty = _fix_shader_material(res) or dirty
+		# ArrayMesh (surface materials embedded)
+		if res is ArrayMesh:
+			for surf in range(res.get_surface_count()):
+				var mat = res.surface_get_material(surf)
+				if mat is ShaderMaterial:
+					if _fix_shader_material(mat):
+						res.surface_set_material(surf, mat)
+						dirty = true
+		if dirty:
+			var err = ResourceSaver.save(res, path)
+			if err == OK:
+				fixed += 1
+				print("FIXED ", path)
+			else:
+				push_error("Failed to save " + path + " (err=" + str(err) + ")")
+	print("Done. checked=", checked, " fixed=", fixed)
+	quit()
+
+func _fix_shader_material(mat: ShaderMaterial) -> bool:
+	if mat.shader == null:
+		return false
+	var old_code: String = mat.shader.code
+	var new_code := old_code
+	for pair in REPLACEMENTS:
+		new_code = new_code.replace(pair[0], pair[1])
+	if new_code == old_code:
+		return false
+	mat.shader.code = new_code
+	return true
+
+func _find_resources(dir_path: String) -> Array:
+	var result := []
+	var dir = DirAccess.open(dir_path)
+	if dir == null:
+		return result
+	dir.list_dir_begin()
+	var name = dir.get_next()
+	while name != "":
+		if name == "." or name == "..":
+			name = dir.get_next()
+			continue
+		var sub = dir_path + "/" + name
+		if dir.current_is_dir():
+			result.append_array(_find_resources(sub))
+		else:
+			for ext in EXTENSIONS:
+				if name.ends_with(ext):
+					result.append(sub)
+					break
+		name = dir.get_next()
+	return result

scripts/migration/migrate_shaders.gd.uid

@@ -0,0 +1 @@
+uid://bajsl67vg36aj

scripts/migration/resave_scenes.gd

@@ -0,0 +1,30 @@
+@tool
+extends SceneTree
+
+# Load and re-save every .tscn so embedded sub-resources (inline ArrayMesh,
+# etc.) are rewritten in the current Godot 4 format.
+
+func _init() -> void:
+	for path in _find("res://scenes", ".tscn"):
+		var res = ResourceLoader.load(path, "", ResourceLoader.CACHE_MODE_IGNORE)
+		if res is PackedScene:
+			if ResourceSaver.save(res, path) == OK:
+				print("RESAVED ", path)
+	quit()
+
+func _find(dir_path: String, ext: String) -> Array:
+	var result := []
+	var dir = DirAccess.open(dir_path)
+	if dir == null:
+		return result
+	dir.list_dir_begin()
+	var name = dir.get_next()
+	while name != "":
+		if name != "." and name != "..":
+			var sub = dir_path + "/" + name
+			if dir.current_is_dir():
+				result.append_array(_find(sub, ext))
+			elif name.ends_with(ext):
+				result.append(sub)
+		name = dir.get_next()
+	return result

scripts/migration/resave_scenes.gd.uid

@@ -0,0 +1 @@
+uid://lnln55ich8ac