chore: fix lint errors — auto-format, isNaN, unused imports, button type

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/routes/admin-tags.test.ts

@@ -64,7 +64,11 @@ describe("Admin Tag Routes", () => {
 			});
 			expect(res.status).toBe(201);
 			const body = await res.json();
-			expect(body).toMatchObject({ id: expect.any(Number), name: "ultralight", parentId: null });
+			expect(body).toMatchObject({
+				id: expect.any(Number),
+				name: "ultralight",
+				parentId: null,
+			});
 		});
 
 		it("creates tag with parentId", async () => {