Make Main, Settings, ChooseScene, and gameplay run in Godot 4.6

Catch-all commit for everything the --convert-3to4 tool missed during a
manual playtest of the game. All errors raised by clicking through Main
-> Puzzles -> level were fixed.

GDScript:
- PackedScene.instance() -> instantiate() (ChooseScene.gd)
- String(x) constructor doesn't exist -> str(x) (MBase, MScene,
  MLevel, Animation, Levels)
- 'x as int/String/bool' doesn't parse strings -> explicit
  int()/str()/bool(int()) (MScene, MLevel, MSetting)
- BaseButton.pressed (property) -> button_pressed; set_pressed() ->
  direct assignment (Settings.gd)
- AnimationPlayer.add_animation() removed -> go through
  AnimationLibrary (Levels.gd)
- PhysicsDirectSpaceState3D.intersect_ray(from, to, ...) ->
  PhysicsRayQueryParameters3D.create() (Levels.gd)
- @export with type-hint-in-comment ('# (String, ...)') -> explicit
  @export_enum (candle.gd)
- Get effective material with get_active_material() instead of
  get_surface_override_material(), with null guard (Levels.gd)
- get_node() -> get_node_or_null() so missing items from ahog.json
  (e.g. sm_super_dager in Home) don't crash (Levels.gd)

Scenes/resources:
- Remove 14 Tween nodes from WarCraft.tscn — Tween is no longer a
  Node in Godot 4. Rewrite Animation.start_dissolve to use
  create_tween().tween_method().
- Rename property material/N -> surface_material_override/N in every
  .tscn (10 files) — Godot 3 -> 4 rename that --convert-3to4 missed.
  Without this, MeshInstance3D.get_active_material(0) returned the
  glTF-imported StandardMaterial3D instead of the project's custom
  dissolve ShaderMaterial.

Shaders:
- One-shot scripts/migrate_shaders.gd walks every .material under
  assets/ and fixes Godot 3 -> 4 shader code in-place. Fixed 17
  materials: depth_draw_alpha_prepass -> depth_prepass_alpha,
  hint_color -> source_color, NORMALMAP -> NORMAL_MAP.

Result: Main, Settings, ChooseScene, and the WarCraft level all run
without script or shader errors. Remaining noise is non-blocking
(visual_shader graph in text_outline.material, baked lightmap binary
format from Godot 3, and empty animation tracks).

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

project.godot

@@ -13,12 +13,13 @@ config_version=5
 config/name="Puzzle Quest"
 config/description="A treasure chest fill with any Jiggsaw !"
 run/main_scene="res://scenes/Main.tscn"
+config/quit_on_go_back=false
+config/features=PackedStringArray("4.6")
+boot_splash/stretch_mode=0
 boot_splash/image="res://releases/splash-screen.png"
-boot_splash/fullsize=false
 config/icon="res://icon.png"
 config/macos_native_icon="res://releases/mac/project.icns"
 config/windows_native_icon="res://releases/windows/project.ico"
-config/quit_on_go_back=false
 
 [autoload]
 
@@ -33,10 +34,9 @@ GlobalAnimation="*res://scripts/Animation.gd"
 window/size/viewport_width=1280
 window/size/viewport_height=720
 window/size/resizable=false
-window/dpi/allow_hidpi=true
-window/handheld/orientation="sensor_landscape"
 window/stretch/mode="2d"
 window/stretch/aspect="expand"
+window/handheld/orientation="sensor_landscape"
 
 [editor_plugins]
 
@@ -58,7 +58,9 @@ scene={
 
 ui_end={
 "deadzone": 0.5,
-"events": [Object(InputEventKey,"resource_local_to_scene":false,"resource_name":"","device":0,"alt_pressed":false,"shift_pressed":false,"ctrl_pressed":false,"meta_pressed":false,"pressed":false,"keycode":4194318,"physical_keycode":0,"unicode":0,"echo":false,"script":null), Object(InputEventKey,"resource_local_to_scene":false,"resource_name":"","device":0,"alt_pressed":false,"shift_pressed":false,"ctrl_pressed":false,"meta_pressed":false,"pressed":false,"keycode":4194305,"physical_keycode":0,"unicode":0,"echo":false,"script":null)]
+"events": [Object(InputEventKey,"resource_local_to_scene":false,"resource_name":"","device":0,"window_id":0,"alt_pressed":false,"shift_pressed":false,"ctrl_pressed":false,"meta_pressed":false,"pressed":false,"keycode":4194318,"physical_keycode":0,"key_label":0,"unicode":0,"location":0,"echo":false,"script":null)
+, Object(InputEventKey,"resource_local_to_scene":false,"resource_name":"","device":0,"window_id":0,"alt_pressed":false,"shift_pressed":false,"ctrl_pressed":false,"meta_pressed":false,"pressed":false,"keycode":4194305,"physical_keycode":0,"key_label":0,"unicode":0,"location":0,"echo":false,"script":null)
+]
 }
 
 [locale]