refactor: migrate to monorepo structure with Docker, PocketBase, and e2e tests

- Reorganize into apps/, packages/, docs/, e2e/, pocketbase/ directories
- Add Dockerfiles for web, worker, and PocketBase services
- Add docker-compose.yml for local orchestration
- Add turbo.json for monorepo task management
- Add Playwright e2e test infrastructure
- Add PocketBase backend with migrations
- Remove Vite/Next.js/ESLint/PostCSS config files
- Update package.json with workspace dependencies
- Add .env.example and .dockerignore

apps/web/lib/stores/use-theme-store.ts

@@ -0,0 +1,41 @@
+import { create } from 'zustand';
+import { persist } from 'zustand/middleware';
+
+type ThemeMode = 'light' | 'dark' | 'system';
+type Density = 'compact' | 'comfortable' | 'spacious';
+
+interface ThemeState {
+  mode: ThemeMode;
+  accent: string;
+  font: string;
+  density: Density;
+  reducedMotion: boolean;
+
+  // Actions
+  setMode: (mode: ThemeMode) => void;
+  setAccent: (color: string) => void;
+  setFont: (font: string) => void;
+  setDensity: (density: Density) => void;
+  setReducedMotion: (enabled: boolean) => void;
+}
+
+export const useThemeStore = create<ThemeState>()(
+  persist(
+    (set) => ({
+      mode: 'system',
+      accent: '#356bff',
+      font: 'geist',
+      density: 'comfortable',
+      reducedMotion: false,
+
+      setMode: (mode) => set({ mode }),
+      setAccent: (accent) => set({ accent }),
+      setFont: (font) => set({ font }),
+      setDensity: (density) => set({ density }),
+      setReducedMotion: (reducedMotion) => set({ reducedMotion }),
+    }),
+    {
+      name: 'project-e-theme',
+    }
+  )
+);