fix: getSession to getDbSession to avoid h3 conflict

backend/utils/session.ts

@@ -47,7 +47,7 @@ export async function createSession(
 /**
  * 세션 조회 (유효한 세션만)
  */
-export async function getSession(sessionId: string): Promise<Session | null> {
+export async function getDbSession(sessionId: string): Promise<Session | null> {
   if (!sessionId) return null
   
   const row = await queryOne<any>(`
@@ -168,7 +168,7 @@ export async function getAuthenticatedUserId(event: any): Promise<number | null>
   // 1. 새로운 세션 토큰 확인
   const sessionId = getSessionIdFromCookie(event)
   if (sessionId) {
-    const session = await getSession(sessionId)
+    const session = await getDbSession(sessionId)
     if (session) {
       await refreshSession(sessionId)
       return session.employeeId