style(auth-files): use neutral colors for credential action buttons

- Remove color accents from refresh, settings, models, delete, details, and import buttons
- Unify borders, text, and hover styles across light and dark themes
- Preserve status colors for badges, usage metrics, and toggles

tests/themePreferences.test.ts

@@ -0,0 +1,59 @@
+import { expect, test } from 'bun:test';
+import { ThemePreferences } from '../src/services/themePreferences';
+import type { ThemePreference } from '../src/themeController';
+
+function storage(initial?: string) {
+  let value = initial ?? null;
+  return { getItem: () => value, setItem: (_key: string, next: string) => { value = next; } } as Storage;
+}
+
+for (const preference of ['light', 'dark', 'system'] as const) {
+  test(`migrates ${preference} and restores it after browser storage is lost`, async () => {
+    let disk: ThemePreference | null = null;
+    const backend = { load: async () => disk, save: async (next: ThemePreference) => { disk = next; } };
+    const first = new ThemePreferences(() => storage(preference));
+    await first.initialize(backend);
+    expect(disk).toBe(preference);
+    const cache = storage();
+    const restarted = new ThemePreferences(() => cache);
+    await restarted.initialize(backend);
+    expect(restarted.get()).toBe(preference);
+    expect(cache.getItem('easy-cli-proxy-api.theme')).toBe(preference);
+  });
+}
+
+test('native preference wins over a stale browser preference', async () => {
+  const preferences = new ThemePreferences(() => storage('light'));
+  await preferences.initialize({ load: async () => 'dark', save: async () => { throw new Error('unexpected write'); } });
+  expect(preferences.get()).toBe('dark');
+});
+
+test('saves with blocked browser storage and serializes rapid changes', async () => {
+  const preferences = new ThemePreferences(() => { throw new Error('blocked'); });
+  const writes: ThemePreference[] = [];
+  await preferences.initialize({ load: async () => null, save: async (next) => { await Promise.resolve(); writes.push(next); } });
+  preferences.set('dark');
+  preferences.set('light');
+  preferences.set('system');
+  await preferences.flush();
+  expect(writes).toEqual(['dark', 'light', 'system']);
+  expect(preferences.get()).toBe('system');
+});
+
+test('a failed native read does not overwrite the saved file', async () => {
+  const preferences = new ThemePreferences(() => storage('dark'));
+  const writes: ThemePreference[] = [];
+  await expect(preferences.initialize({ load: async () => { throw new Error('unreadable'); }, save: async (next) => { writes.push(next); } })).rejects.toThrow('unreadable');
+  expect(preferences.get()).toBe('dark');
+  preferences.set('light');
+  await preferences.flush();
+  expect(writes).toEqual([]);
+});
+
+test('missing preferences use system without writing a default', async () => {
+  const preferences = new ThemePreferences(() => storage('invalid'));
+  const writes: ThemePreference[] = [];
+  await preferences.initialize({ load: async () => null, save: async (next) => { writes.push(next); } });
+  expect(preferences.get()).toBe('system');
+  expect(writes).toEqual([]);
+});