Show leave button and spinner while requesting to join call link

ts/components/SpinnerV2.tsx

@@ -0,0 +1,40 @@
+// Copyright 2024 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import React from 'react';
+import classNames from 'classnames';
+
+export const SpinnerSvgSizes = ['small', 'normal'] as const;
+export type SpinnerSvgSize = typeof SpinnerSvgSizes[number];
+
+export type Props = {
+  className?: string;
+  size: number;
+  strokeWidth: number;
+};
+
+export function SpinnerV2({
+  className,
+  size,
+  strokeWidth,
+}: Props): JSX.Element {
+  return (
+    <svg
+      className={classNames('SpinnerV2', className)}
+      viewBox={`0 0 ${size * 2} ${size * 2}`}
+      style={{
+        height: size,
+        width: size,
+      }}
+    >
+      <circle
+        className="SpinnerV2__Path"
+        cx={size}
+        cy={size}
+        r={size * 0.8}
+        fill="none"
+        strokeWidth={strokeWidth}
+      />
+    </svg>
+  );
+}