Finish JerryScript Entity/Scene wiring; remove JSON serialize/deserialize

Register Entity, the generic Component wrapper, and Scene as JerryScript
classes (modulelist.c ties them together, plus their .d.ts stubs), so
scenes/entities can be built from script going forward instead of the
JSON scene format.

With scripting now the intended authoring path, drop the JSON
serialize/deserialize machinery entirely: componentdefinition_t's
serialize/deserialize callbacks, every component's *Serialize/
*Deserialize function, entitySerialize/entityDeserialize,
sceneSerialize/sceneDeserialize, and the "prefabs/<name>.json"/
"scenes/<name>.json" asset fallback in entityPrefabResolveAndApply/
scenePrefabResolveAndApply (C-coded prefabs only now). physicsshape.c
and its test are removed outright since they only existed for this.
game.c's test scene now comes from the existing overworldSceneCreate()
C builder instead of loading the now-deleted assets/scenes/test.json.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

types/entity/component/component.d.ts

@@ -0,0 +1,36 @@
+// Copyright (c) 2026 Dominic Masters
+//
+// This software is released under the MIT License.
+// https://opensource.org/licenses/MIT
+
+/**
+ * A component attached to an Entity. Generic across every component
+ * type for now -- there are no typed per-type properties yet (e.g. no
+ * `.position` on a POSITION component), just the operations every
+ * component supports regardless of type. Only ever obtained via
+ * Entity.add()/Entity.getComponent(), never constructed directly.
+ */
+declare class Component {
+  /** The componenttype_t this component was added as, e.g. POSITION. */
+  readonly type: number;
+
+  /** The id of the Entity this component belongs to. */
+  readonly entityId: number;
+
+  /** Removes this component from its entity. */
+  dispose(): void;
+}
+
+/**
+ * Component type constants, usable with Entity.add()/getComponent().
+ * The numeric values are opaque/build-specific; treat the names as the
+ * stable API.
+ */
+declare const POSITION: number;
+declare const CAMERA: number;
+declare const RENDERABLE: number;
+declare const PHYSICS: number;
+declare const TRIGGER: number;
+declare const ANIMATION: number;
+declare const PLAYER: number;
+declare const INTERACTABLE: number;

types/entity/entity.d.ts

@@ -0,0 +1,36 @@
+// Copyright (c) 2026 Dominic Masters
+//
+// This software is released under the MIT License.
+// https://opensource.org/licenses/MIT
+
+/// <reference path="component/component.d.ts" />
+
+/**
+ * A game entity. `new Entity()` adds it to the currently active scene's
+ * entity manager (see Scene.getActive()) -- throws if no scene is
+ * active.
+ */
+declare class Entity {
+  constructor();
+
+  /** The engine-assigned numeric entity ID. */
+  readonly id: number;
+
+  /** Optional name; empty string if unset. */
+  name: string;
+
+  /**
+   * Adds a component of the given type (e.g. POSITION) to this entity
+   * and returns its wrapper.
+   */
+  add(type: number): Component;
+
+  /**
+   * Gets this entity's component of the given type, or undefined if it
+   * doesn't have one.
+   */
+  getComponent(type: number): Component | undefined;
+
+  /** Removes this entity and all its position-component descendants. */
+  dispose(): void;
+}

types/index.d.ts

@@ -0,0 +1,8 @@
+// Copyright (c) 2026 Dominic Masters
+//
+// This software is released under the MIT License.
+// https://opensource.org/licenses/MIT
+
+/// <reference path="entity/entity.d.ts" />
+/// <reference path="entity/component/component.d.ts" />
+/// <reference path="scene/scene.d.ts" />

types/scene/scene.d.ts

@@ -0,0 +1,27 @@
+// Copyright (c) 2026 Dominic Masters
+//
+// This software is released under the MIT License.
+// https://opensource.org/licenses/MIT
+
+/**
+ * A scene: an isolated pool of entities/components. `new Scene()`
+ * creates an empty scene -- it is not made active automatically, call
+ * `.setActive()` for that. `Entity`/`Component` always operate on
+ * whichever scene is currently active, not on a specific Scene
+ * instance.
+ */
+declare class Scene {
+  constructor();
+
+  /** The engine-assigned numeric scene ID. */
+  readonly id: number;
+
+  /** Makes this the active scene (see Scene.getActive()). */
+  setActive(): void;
+
+  /** Destroys this scene and all its entities/components. */
+  dispose(): void;
+
+  /** Gets the currently active scene, or undefined if none is active. */
+  static getActive(): Scene | undefined;
+}