chore: Move to Typescript (#2783)

This PR moves the entire project to Typescript. Due to the ~1000 ignores this will lead to a messy codebase for a while, but the churn is worth it – all of those ignore comments are places that were never type-safe previously.

closes #1282

app/components/Avatar/Avatar.tsx

@@ -0,0 +1,71 @@
+import { observable } from "mobx";
+import { observer } from "mobx-react";
+import * as React from "react";
+import styled from "styled-components";
+import User from "~/models/User";
+import placeholder from "./placeholder.png";
+
+type Props = {
+  src: string;
+  size: number;
+  icon?: React.ReactNode;
+  user?: User;
+  alt?: string;
+  onClick?: () => void;
+  className?: string;
+};
+
+@observer
+class Avatar extends React.Component<Props> {
+  @observable
+  error: boolean;
+
+  static defaultProps = {
+    size: 24,
+  };
+
+  handleError = () => {
+    this.error = true;
+  };
+
+  render() {
+    const { src, icon, ...rest } = this.props;
+    return (
+      <AvatarWrapper>
+        <CircleImg
+          onError={this.handleError}
+          src={this.error ? placeholder : src}
+          {...rest}
+        />
+        {icon && <IconWrapper>{icon}</IconWrapper>}
+      </AvatarWrapper>
+    );
+  }
+}
+
+const AvatarWrapper = styled.div`
+  position: relative;
+`;
+
+const IconWrapper = styled.div`
+  display: flex;
+  position: absolute;
+  bottom: -2px;
+  right: -2px;
+  background: ${(props) => props.theme.primary};
+  border: 2px solid ${(props) => props.theme.background};
+  border-radius: 100%;
+  width: 20px;
+  height: 20px;
+`;
+
+const CircleImg = styled.img<{ size: number }>`
+  display: block;
+  width: ${(props) => props.size}px;
+  height: ${(props) => props.size}px;
+  border-radius: 50%;
+  border: 2px solid ${(props) => props.theme.background};
+  flex-shrink: 0;
+`;
+
+export default Avatar;