feat(admin): web admin panel — user CRUD, role assignment, system health (#150)

Co-authored-by: Jason Woltje <jason@diversecanvas.com>
Co-committed-by: Jason Woltje <jason@diversecanvas.com>

packages/auth/src/auth.ts

@@ -1,6 +1,6 @@
 import { betterAuth } from 'better-auth';
 import { drizzleAdapter } from 'better-auth/adapters/drizzle';
-import { genericOAuth } from 'better-auth/plugins';
+import { admin, genericOAuth } from 'better-auth/plugins';
 import type { Db } from '@mosaic/db';
 
 export interface AuthConfig {
@@ -68,7 +68,7 @@ export function createAuth(config: AuthConfig) {
       expiresIn: 60 * 60 * 24 * 7, // 7 days
       updateAge: 60 * 60 * 24, // refresh daily
     },
-    plugins,
+    plugins: [...(plugins ?? []), admin({ defaultRole: 'member', adminRoles: ['admin'] })],
   });
 }