add create card instance command

packages/host/app/commands/create-card-instance.ts

@@ -0,0 +1,42 @@
+import { service } from '@ember/service';
+
+import { type LooseSingleCardDocument } from '@cardstack/runtime-common';
+
+import type * as BaseCommandModule from 'https://cardstack.com/base/command';
+
+import HostBaseCommand from '../lib/host-base-command';
+
+import CardService from '../services/card-service';
+
+export default class CreateCardInstanceCommand extends HostBaseCommand<
+  typeof BaseCommandModule.CreateInstanceInput
+> {
+  @service declare private cardService: CardService;
+
+  description = `Create a new card instance given a card ref and realm.`;
+
+  async getInputType() {
+    let commandModule = await this.loadCommandModule();
+    const { CreateInstanceInput } = commandModule;
+    return CreateInstanceInput;
+  }
+
+  protected async run(
+    input: BaseCommandModule.CreateInstanceInput,
+  ): Promise<undefined> {
+    if (!input.module || !input.realm) {
+      throw new Error(
+        "Create instance command can't run because it doesn't have all the fields in arguments returned by open ai",
+      );
+    }
+    let doc: LooseSingleCardDocument = {
+      data: {
+        meta: {
+          adoptsFrom: input.module,
+          realmURL: input.realm,
+        },
+      },
+    };
+    await this.cardService.createFromSerialized(doc.data, doc);
+  }
+}