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/Key.ts

@@ -0,0 +1,18 @@
+import styled from "styled-components";
+
+const Key = styled.kbd`
+  display: inline-block;
+  padding: 4px 6px;
+  font: 11px "SFMono-Regular", Consolas, "Liberation Mono", Menlo, Courier,
+    monospace;
+  line-height: 10px;
+  color: ${(props) => props.theme.almostBlack};
+  vertical-align: middle;
+  background-color: ${(props) => props.theme.smokeLight};
+  border: solid 1px ${(props) => props.theme.slateLight};
+  border-bottom-color: ${(props) => props.theme.slate};
+  border-radius: 3px;
+  box-shadow: inset 0 -1px 0 ${(props) => props.theme.slate};
+`;
+
+export default Key;