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-supabase/package.json

@@ -0,0 +1,24 @@
+{
+  "name": "@manacore/shared-supabase",
+  "version": "0.1.0",
+  "private": true,
+  "description": "Shared Supabase client and utilities for Manacore monorepo",
+  "main": "./src/index.ts",
+  "types": "./src/index.ts",
+  "exports": {
+    ".": "./src/index.ts"
+  },
+  "scripts": {
+    "type-check": "tsc --noEmit",
+    "clean": "rm -rf dist"
+  },
+  "dependencies": {
+    "@supabase/supabase-js": "^2.81.1"
+  },
+  "devDependencies": {
+    "typescript": "^5.9.2"
+  },
+  "peerDependencies": {
+    "@manacore/shared-types": "workspace:*"
+  }
+}

packages/shared-supabase/src/index.ts

@@ -0,0 +1,62 @@
+/**
+ * Shared Supabase utilities for Manacore monorepo
+ *
+ * This package provides a unified Supabase client and common database utilities.
+ */
+
+import { createClient, SupabaseClient } from '@supabase/supabase-js';
+import type { SupabaseConfig } from '@manacore/shared-types';
+
+export { SupabaseClient } from '@supabase/supabase-js';
+
+/**
+ * Create a Supabase client with the given configuration
+ */
+export function createSupabaseClient(config: SupabaseConfig): SupabaseClient {
+  return createClient(config.url, config.anonKey, {
+    auth: {
+      persistSession: true,
+      autoRefreshToken: true,
+    },
+  });
+}
+
+/**
+ * Create a Supabase admin client with service role key
+ */
+export function createSupabaseAdminClient(config: SupabaseConfig): SupabaseClient {
+  if (!config.serviceRoleKey) {
+    throw new Error('Service role key is required for admin client');
+  }
+
+  return createClient(config.url, config.serviceRoleKey, {
+    auth: {
+      persistSession: false,
+      autoRefreshToken: false,
+    },
+  });
+}
+
+/**
+ * Common database query helpers
+ */
+export const dbHelpers = {
+  /**
+   * Handle Supabase query result and return standardized response
+   */
+  handleQueryResult<T>(result: { data: T | null; error: any }): {
+    data: T | null;
+    error: { message: string; code?: string } | null;
+  } {
+    if (result.error) {
+      return {
+        data: null,
+        error: {
+          message: result.error.message,
+          code: result.error.code,
+        },
+      };
+    }
+    return { data: result.data, error: null };
+  },
+};

packages/shared-supabase/tsconfig.json

@@ -0,0 +1,17 @@
+{
+  "compilerOptions": {
+    "target": "ES2020",
+    "module": "ESNext",
+    "moduleResolution": "bundler",
+    "lib": ["ES2020"],
+    "strict": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "forceConsistentCasingInFileNames": true,
+    "declaration": true,
+    "declarationMap": true,
+    "outDir": "./dist"
+  },
+  "include": ["src/**/*"],
+  "exclude": ["node_modules", "dist"]
+}