feat: implement lobby functionality with user and server information retrieval

app/gateway-api/src/auth/inMemoryUserRepository.ts

@@ -12,6 +12,14 @@ export const createInMemoryUserRepository = (
     const usersByEmail = new Map<string, UserRecord>();
 
     return {
+        async findById(id: string): Promise<UserRecord | null> {
+            for (const user of usersByName.values()) {
+                if (user.id === id) {
+                    return user;
+                }
+            }
+            return null;
+        },
         async findByUsername(username: string): Promise<UserRecord | null> {
             return usersByName.get(username) ?? null;
         },

app/gateway-api/src/auth/postgresUserRepository.ts

@@ -56,6 +56,14 @@ export const createPostgresUserRepository = (
     hasher: PasswordHasher = createSimplePasswordHasher()
 ): UserRepository => {
     return {
+        async findById(id: string): Promise<UserRecord | null> {
+            const row = await prisma.appUser.findUnique({
+                where: {
+                    id,
+                },
+            });
+            return row ? mapUser(row) : null;
+        },
         async findByUsername(username: string): Promise<UserRecord | null> {
             const row = await prisma.appUser.findUnique({
                 where: {

app/gateway-api/src/auth/userRepository.ts

@@ -51,6 +51,7 @@ export interface CreateUserInput {
 }
 
 export interface UserRepository {
+    findById(id: string): Promise<UserRecord | null>;
     findByUsername(username: string): Promise<UserRecord | null>;
     findByOauthId(type: 'KAKAO', oauthId: string): Promise<UserRecord | null>;
     findByEmail(email: string): Promise<UserRecord | null>;