Add tests to all packages, remove passWithNoTests

Every package now has tests — no more empty test suites:

- map-core: 33 tests — maxspeedColor, routeGradeColor, elevationColor,
  POI categories, getCategoriesForProfile, tile layer configs
- db: 5 tests — withDb error handling (503 on DB error, re-throws
  Response/DataWithResponseInit, logs errors)
- ui: 14 tests — Button variants/sizes/disabled, Input label/id/error,
  Card className forwarding
- map: 2 tests — baseLayers/overlayLayers re-export verification

Remove passWithNoTests from vitest.shared.ts so missing tests are
caught immediately when adding new packages.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/map/src/index.test.ts

@@ -0,0 +1,19 @@
+/**
+ * @vitest-environment jsdom
+ */
+import { describe, it, expect } from "vitest";
+import { baseLayers, overlayLayers } from "./index.ts";
+
+describe("map package exports", () => {
+  it("re-exports baseLayers from map-core", () => {
+    expect(baseLayers).toBeDefined();
+    expect(baseLayers.length).toBeGreaterThan(0);
+    expect(baseLayers[0]!.name).toBe("OpenStreetMap");
+  });
+
+  it("re-exports overlayLayers from map-core", () => {
+    expect(overlayLayers).toBeDefined();
+    expect(overlayLayers.length).toBeGreaterThan(0);
+    expect(overlayLayers.every((l) => l.id)).toBe(true);
+  });
+});