improve loading states:

* app loader
 * specific loaders with spinner

app/core/components/spinner.module.css

@@ -0,0 +1,15 @@
+.ring {
+	display: inline-block;
+	width: 50px;
+	height: 50px;
+	border: 3px solid rgba(0, 0, 0, 0.15);
+	border-radius: 50%;
+	border-top-color: currentColor;
+	animation: spin 1s ease-in-out infinite;
+}
+
+@keyframes spin {
+	to {
+		transform: rotate(360deg);
+	}
+}

app/core/components/spinner.tsx

@@ -0,0 +1,11 @@
+import clsx from "clsx";
+
+import styles from "./spinner.module.css";
+
+export default function Spinner() {
+	return (
+		<div className="h-full flex">
+			<div className={clsx(styles.ring, "m-auto text-primary-400")} />
+		</div>
+	);
+}