fix: resolve build failures in PR #236

- Add missing Zod import in lib/auth.ts
- Fix Zod error handling to use 'issues' property instead of 'errors'

The build was failing due to missing import and incorrect Zod API usage.
Build now passes locally.

Author: mchestr

lib/auth.ts

@@ -4,6 +4,7 @@ import { prisma } from "@/lib/prisma"
 import { createLogger } from "@/lib/utils/logger"
 import { NextAuthOptions } from "next-auth"
 import CredentialsProvider from "next-auth/providers/credentials"
+import { z } from "zod"
 
 const logger = createLogger("AUTH")
 

lib/jellyfin-auth.ts

@@ -57,7 +57,7 @@ export async function authenticateJellyfin(
   // Validate credentials
   const validation = JellyfinCredentialsSchema.safeParse({ username, password })
   if (!validation.success) {
-    const errors = validation.error.errors.map(e => e.message).join(", ")
+    const errors = validation.error.issues.map(e => e.message).join(", ")
     logger.warn("Invalid Jellyfin credentials format", { errors })
     return {
       success: false,