feat: add privacy, terms, and cookies pages

Footer and login legal links were stubs. Point them at real marketing
pages that follow the Figma content-page template.

tests/components/LoginForm.test.tsx

@@ -76,6 +76,16 @@ describe("LoginForm", () => {
     ).toBeInTheDocument();
   });
 
+  it("links terms and privacy to the legal pages", () => {
+    renderLoginForm();
+    expect(
+      screen.getByRole("link", { name: "Terms of Service" }),
+    ).toHaveAttribute("href", "/terms");
+    expect(
+      screen.getByRole("link", { name: "Privacy Policy" }),
+    ).toHaveAttribute("href", "/privacy");
+  });
+
   it("shows validation error when email is invalid", async () => {
     const user = userEvent.setup();
     renderLoginForm();