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

server/presenters/user.test.ts

@@ -0,0 +1,18 @@
+import presentUser from "./user";
+
+it("presents a user", async () => {
+  const user = presentUser({
+    id: "123",
+    name: "Test User",
+    username: "testuser",
+  });
+  expect(user).toMatchSnapshot();
+});
+it("presents a user without slack data", async () => {
+  const user = presentUser({
+    id: "123",
+    name: "Test User",
+    username: "testuser",
+  });
+  expect(user).toMatchSnapshot();
+});