Add cache for markdown card and markdown element (#24217)

* Add cache for markdown card and markdown element

* Rename to expiration

* Only use cache logic for markdown card

* Add tests

* Improve tests

test/util/cache-manager.test.ts

@@ -0,0 +1,50 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
+import { CacheManager } from "../../src/util/cache-manager";
+
+const savedSetTimeout = setTimeout;
+
+describe("cache-manager", () => {
+  beforeEach(() => {
+    vi.useFakeTimers();
+    window.setTimeout = setTimeout;
+  });
+  afterEach(() => {
+    vi.useRealTimers();
+    window.setTimeout = savedSetTimeout;
+  });
+  it("should return value before expiration", async () => {
+    const cacheManager = new CacheManager<string>(1000);
+    cacheManager.set("key", "value");
+
+    expect(cacheManager.has("key")).toBe(true);
+    expect(cacheManager.get("key")).toBe("value");
+
+    vi.advanceTimersByTime(500);
+    expect(cacheManager.has("key")).toBe(true);
+    expect(cacheManager.get("key")).toBe("value");
+  });
+
+  it("should not return value after expiration", async () => {
+    const cacheManager = new CacheManager<string>(1000);
+    cacheManager.set("key", "value");
+
+    expect(cacheManager.has("key")).toBe(true);
+    expect(cacheManager.get("key")).toBe("value");
+
+    vi.advanceTimersByTime(2000);
+    expect(cacheManager.has("key")).toBe(false);
+    expect(cacheManager.get("key")).toBe(undefined);
+  });
+
+  it("should always return value if no expiration", async () => {
+    const cacheManager = new CacheManager<string>();
+    cacheManager.set("key", "value");
+
+    expect(cacheManager.has("key")).toBe(true);
+    expect(cacheManager.get("key")).toBe("value");
+
+    vi.advanceTimersByTime(10000000000000000000000);
+    expect(cacheManager.has("key")).toBe(true);
+    expect(cacheManager.get("key")).toBe("value");
+  });
+});