Local file storage (#5763)

Co-authored-by: Tom Moor <tom.moor@gmail.com>

server/models/Attachment.test.ts

@@ -0,0 +1,10 @@
+import { buildAttachment } from "@server/test/factories";
+import Attachment from "./Attachment";
+
+describe("#findByKey", () => {
+  it("should return the correct attachment given a key", async () => {
+    const attachment = await buildAttachment();
+    const found = await Attachment.findByKey(attachment.key);
+    expect(found?.id).toBe(attachment.id);
+  });
+});