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/utils/urls.test.ts

@@ -0,0 +1,13 @@
+import { decodeURIComponentSafe } from "./urls";
+
+describe("decodeURIComponentSafe", () => {
+  test("to handle % symbols", () => {
+    expect(decodeURIComponentSafe("%")).toBe("%");
+    expect(decodeURIComponentSafe("%25")).toBe("%");
+  });
+
+  test("to correctly account for encoded symbols", () => {
+    expect(decodeURIComponentSafe("%7D")).toBe("}");
+    expect(decodeURIComponentSafe("%2F")).toBe("/");
+  });
+});