refactor!: migrate away from bun

- migrate package management to pnpm
- migrate test suite to vitest
- also remove Anify integration

src/libs/fetchFromMultipleSources.spec.ts

@@ -1,10 +1,10 @@
-import { describe, expect, it } from "bun:test";
+import { describe, expect, it } from "vitest";
 
 import { fetchFromMultipleSources } from "./fetchFromMultipleSources";
 
 describe("fetchFromMultipleSources", () => {
-  it("no promises, throws exception", () => {
-    expect(() => fetchFromMultipleSources([])).toThrow(
+  it("no promises, throws exception", async () => {
+    await expect(fetchFromMultipleSources([])).rejects.toThrow(
       "fetchPromises cannot be empty",
     );
   });
@@ -30,7 +30,7 @@ describe("fetchFromMultipleSources", () => {
       () => Promise.resolve(3),
     ]);
 
-    expect(errorOccurred).toBeFalse();
+    expect(errorOccurred).toBe(false);
   });
 
   it("has promises that all throw, returns null", async () => {
@@ -48,7 +48,7 @@ describe("fetchFromMultipleSources", () => {
       () => Promise.reject(new Error("error")),
     ]);
 
-    expect(errorOccurred).toBeTrue();
+    expect(errorOccurred).toBe(true);
   });
 
   it("has promises but cache has value, returns cached value", async () => {
@@ -80,7 +80,7 @@ describe("fetchFromMultipleSources", () => {
       },
     );
 
-    expect(errorOccurred).toBeFalse();
+    expect(errorOccurred).toBe(false);
   });
 
   it("has promises, no cached value, no valid response, should not save in cache", async () => {