REFACTOR: rename folder data/items -> data/item

REFACTOR: rename folder `data/messages` -> `data/chat-message`.

module/data/item/base.mjs

@@ -0,0 +1,43 @@
+/**
+ * @typedef {Object} ItemDataModelMetadata
+ * @property {String} type - System type that this type data model represents
+ * @property {Boolean} hasDescription
+ */
+
+const fields = foundry.data.fields;
+
+export default class BaseDataItem extends foundry.abstract.TypeDataModel {
+  /** @returns {ItemDataModelMetadata}*/
+  static get metadata() {
+    return {
+      label: "Base Item",
+      type: "base",
+      hasDescription: false,
+      isQuantifiable: false
+    };
+  }
+
+  /** @inheritDoc */
+  static defineSchema() {
+    const schema = {};
+
+    if (this.metadata.hasDescription)
+      schema.description = new fields.HTMLField({ required: true, nullable: true });
+
+    if (this.metadata.isQuantifiable)
+      schema.quantity = new fields.NumberField({ integer: true, initial: 1, min: 0, required: true });
+
+    return schema;
+  }
+
+  /**
+   * Obtain a data object used to evaluate any dice rolls associated with this Item
+   * @param {object} [options]
+   * @returns {object}
+   */
+  getRollData(options = {}) {
+    const actorRollData = this.parent.actor?.getRollData() ?? {};
+    const data = { ...actorRollData, item: { ...this } };
+    return data;
+  }
+}