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/utils/parseImages.test.ts

@@ -0,0 +1,19 @@
+import parseImages from "./parseImages";
+
+it("should not return non images", () => {
+  expect(parseImages(`# Header`).length).toBe(0);
+});
+it("should return an array of images", () => {
+  const result = parseImages(`# Header
+  
+  ![internal](/attachments/image.png)
+  `);
+  expect(result.length).toBe(1);
+  expect(result[0]).toBe("/attachments/image.png");
+});
+it("should not return non document links", () => {
+  expect(parseImages(`[google](http://www.google.com)`).length).toBe(0);
+});
+it("should not return non document relative links", () => {
+  expect(parseImages(`[relative](/developers)`).length).toBe(0);
+});