Hide client behind context.

Use idb for saving data.
Allow logins.

src/pages/login/forms/FormCreate.tsx

@@ -1,12 +1,15 @@
-import { RevoltClient } from "../../../context/revoltjs/RevoltClient";
+import { AppContext } from "../../../context/revoltjs/RevoltClient";
+import { useContext } from "preact/hooks";
 import { Form } from "./Form";
 
 export function FormCreate() {
+    const { client } = useContext(AppContext);
+
     return (
         <Form
             page="create"
             callback={async data => {
-                await RevoltClient.register(process.env.API_SERVER as string, data);
+                await client.register(import.meta.env.VITE_API_URL, data);
             }}
         />
     );