feat: web setup wizard + admin config/state dir split (#226)

lib/auth/crypto.ts

@@ -1,6 +1,6 @@
 import { createCipheriv, createDecipheriv, randomBytes, createHash } from 'node:crypto';
 import { logger } from '@/lib/logger';
-import { readFileEnv } from '@/lib/read-file-env';
+import { getSessionSecret } from '@/lib/auth/session-secret';
 
 const ALGORITHM = 'aes-256-gcm';
 const IV_LENGTH = 12;
@@ -9,7 +9,7 @@ const TAG_LENGTH = 16;
 const MIN_SECRET_LENGTH = 32;
 
 function getKey(): Buffer {
-  const secret =  process.env.SESSION_SECRET || readFileEnv(process.env.SESSION_SECRET_FILE);
+  const secret = getSessionSecret();
   if (!secret) throw new Error('SESSION_SECRET not configured');
   if (secret.length < MIN_SECRET_LENGTH) {
     throw new Error(