test: add unit and component tests across the monorepo

Adds ~1000 tests to bring the previously-untested packages and apps
under coverage:

- packages/utils — string, color, date, file, level, locale, sanitize,
  field, html, network-icons, rate-limit, url, url-security, monorepo,
  resume/patch, resume/docx/link-utils, style helpers (~97% on the
  testable utility files)
- packages/ui — 28 component test files plus the use-controlled-state,
  use-mobile, use-confirm, use-prompt hooks (95% statements)
- packages/pdf — shared template helpers (filtering, columns, picture,
  metrics, section-links, page-size, rich-text-html, section-title)
- packages/schema — resumeDataSchema, page, templates, default
- packages/fonts — expanded coverage on font helpers
- packages/ai — resume sanitize and extraction template
- packages/api — resume-access-policy
- apps/web — error-message, locale, theme, pwa, dialogs/store, and
  the resume/move-item / section-actions / make-section-item helpers

Adds jsdom polyfills (ResizeObserver, IntersectionObserver,
scrollIntoView, matchMedia) and an explicit React Testing Library
cleanup hook to vitest.setup.ts so portal- and overlay-based components
work without per-test setup.

packages/utils/src/file.test.ts

@@ -0,0 +1,132 @@
+/**
+ * @vitest-environment jsdom
+ */
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import { downloadFromUrl, downloadWithAnchor, generateFilename } from "./file";
+
+describe("generateFilename", () => {
+	it("slugifies the prefix without extension", () => {
+		expect(generateFilename("My Resume")).toBe("my-resume");
+	});
+
+	it("appends extension when provided", () => {
+		expect(generateFilename("My Resume", "pdf")).toBe("my-resume.pdf");
+	});
+
+	it("appends extension verbatim (no extra dot)", () => {
+		expect(generateFilename("Name", "json")).toBe("name.json");
+	});
+
+	it("handles empty extension as no extension", () => {
+		expect(generateFilename("foo", "")).toBe("foo");
+	});
+
+	it("strips diacritics", () => {
+		expect(generateFilename("Résumé", "pdf")).toBe("resume.pdf");
+	});
+
+	it("handles empty prefix", () => {
+		expect(generateFilename("", "pdf")).toBe(".pdf");
+	});
+});
+
+describe("downloadWithAnchor", () => {
+	let createObjectURLSpy: ReturnType<typeof vi.fn>;
+	let revokeObjectURLSpy: ReturnType<typeof vi.fn>;
+	let originalCreate: typeof URL.createObjectURL;
+	let originalRevoke: typeof URL.revokeObjectURL;
+
+	beforeEach(() => {
+		vi.useFakeTimers();
+		originalCreate = URL.createObjectURL;
+		originalRevoke = URL.revokeObjectURL;
+		createObjectURLSpy = vi.fn(() => "blob:mock-url");
+		revokeObjectURLSpy = vi.fn();
+		URL.createObjectURL = createObjectURLSpy;
+		URL.revokeObjectURL = revokeObjectURLSpy;
+	});
+
+	afterEach(() => {
+		vi.useRealTimers();
+		URL.createObjectURL = originalCreate;
+		URL.revokeObjectURL = originalRevoke;
+	});
+
+	it("creates an anchor with correct href, rel, and download attributes", () => {
+		const blob = new Blob(["hello"], { type: "text/plain" });
+		const clickSpy = vi.spyOn(HTMLAnchorElement.prototype, "click").mockImplementation(() => {});
+
+		downloadWithAnchor(blob, "test.txt");
+
+		expect(createObjectURLSpy).toHaveBeenCalledWith(blob);
+		expect(clickSpy).toHaveBeenCalledOnce();
+
+		clickSpy.mockRestore();
+	});
+
+	it("removes the anchor from the DOM after click", () => {
+		const blob = new Blob(["hello"]);
+		vi.spyOn(HTMLAnchorElement.prototype, "click").mockImplementation(() => {});
+
+		const beforeChildCount = document.body.childElementCount;
+		downloadWithAnchor(blob, "test.txt");
+		const afterChildCount = document.body.childElementCount;
+
+		expect(afterChildCount).toBe(beforeChildCount);
+	});
+
+	it("revokes the object URL after 5 seconds", () => {
+		const blob = new Blob(["hello"]);
+		vi.spyOn(HTMLAnchorElement.prototype, "click").mockImplementation(() => {});
+
+		downloadWithAnchor(blob, "test.txt");
+
+		expect(revokeObjectURLSpy).not.toHaveBeenCalled();
+		vi.advanceTimersByTime(4999);
+		expect(revokeObjectURLSpy).not.toHaveBeenCalled();
+		vi.advanceTimersByTime(1);
+		expect(revokeObjectURLSpy).toHaveBeenCalledWith("blob:mock-url");
+	});
+});
+
+describe("downloadFromUrl", () => {
+	let originalFetch: typeof global.fetch;
+	let createObjectURLSpy: ReturnType<typeof vi.fn>;
+	let revokeObjectURLSpy: ReturnType<typeof vi.fn>;
+	let originalCreate: typeof URL.createObjectURL;
+	let originalRevoke: typeof URL.revokeObjectURL;
+
+	beforeEach(() => {
+		originalFetch = global.fetch;
+		originalCreate = URL.createObjectURL;
+		originalRevoke = URL.revokeObjectURL;
+		createObjectURLSpy = vi.fn(() => "blob:mock-url");
+		revokeObjectURLSpy = vi.fn();
+		URL.createObjectURL = createObjectURLSpy;
+		URL.revokeObjectURL = revokeObjectURLSpy;
+	});
+
+	afterEach(() => {
+		global.fetch = originalFetch;
+		URL.createObjectURL = originalCreate;
+		URL.revokeObjectURL = originalRevoke;
+	});
+
+	it("fetches the URL and downloads the resulting blob", async () => {
+		const mockBlob = new Blob(["data"], { type: "application/pdf" });
+		global.fetch = vi.fn(() =>
+			Promise.resolve(new Response(mockBlob, { status: 200 })),
+		) as unknown as typeof global.fetch;
+		vi.spyOn(HTMLAnchorElement.prototype, "click").mockImplementation(() => {});
+
+		await downloadFromUrl("https://example.com/file.pdf", "file.pdf");
+
+		expect(global.fetch).toHaveBeenCalledWith("https://example.com/file.pdf");
+		expect(createObjectURLSpy).toHaveBeenCalled();
+	});
+
+	it("propagates fetch errors", async () => {
+		global.fetch = vi.fn(() => Promise.reject(new Error("network down"))) as unknown as typeof global.fetch;
+		await expect(downloadFromUrl("https://example.com", "x.pdf")).rejects.toThrow("network down");
+	});
+});