feat: add monorepo configuration and shared packages structure

Root-level setup:
- package.json with Turborepo scripts
- pnpm-workspace.yaml for workspace management
- turbo.json for build pipeline
- Common config files (.nvmrc, .prettierrc, .editorconfig)

Shared packages (packages/):
- @manacore/shared-types - Common TypeScript types
- @manacore/shared-supabase - Unified Supabase client
- @manacore/shared-utils - Date, string, async utilities
- @manacore/shared-ui - React Native UI components (placeholder)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

packages/shared-types/src/index.ts

@@ -0,0 +1,47 @@
+/**
+ * Shared types for Manacore monorepo
+ *
+ * This package contains common TypeScript types used across all projects.
+ */
+
+// Common user types
+export interface User {
+  id: string;
+  email: string;
+  created_at: string;
+  updated_at: string;
+}
+
+// Common API response types
+export interface ApiResponse<T> {
+  data: T | null;
+  error: ApiError | null;
+}
+
+export interface ApiError {
+  message: string;
+  code?: string;
+  status?: number;
+}
+
+// Pagination types
+export interface PaginationParams {
+  page?: number;
+  limit?: number;
+  offset?: number;
+}
+
+export interface PaginatedResponse<T> {
+  data: T[];
+  total: number;
+  page: number;
+  limit: number;
+  hasMore: boolean;
+}
+
+// Supabase common types
+export interface SupabaseConfig {
+  url: string;
+  anonKey: string;
+  serviceRoleKey?: string;
+}