fix: inline getDatabasePath into Database.php, delete config/config.php

- Remove require_once for config/config.php (file was never deployed — outside app/)
- Inline DB path resolution directly in Database::determineDatabasePath()
- Uses APP_ROOT when defined (bootstrap already loaded), falls back to __DIR__/../
- DB_ENV=test|prod env-var override preserved for tests
- php -S cli-server -> test.db, nginx/fpm -> posterg.db

app/src/Database.php

@@ -1,7 +1,5 @@
 <?php
 
-require_once __DIR__ . '/../../config/config.php';
-
 /**
  * Unified Database connection class for Post-ERG thesis database
  * Combines functionality from both front-backend and formulaire
@@ -36,18 +34,25 @@ class Database {
     }
 
     /**
-     * Determine database path
-     * Uses centralized config from config.php
-     * Priority: custom path > config.php settings
+     * Determine database path.
+     * Priority: explicit override → DB_ENV env-var → sapi auto-detect.
+     * APP_ROOT is defined by bootstrap.php before any controller loads Database.
      */
-    private function determineDatabasePath($customPath = null) {
-        // Allow explicit override
+    private function determineDatabasePath($customPath = null): string {
         if ($customPath !== null && file_exists($customPath)) {
             return $customPath;
         }
 
-        // Use centralized configuration
-        return getDatabasePath();
+        $root    = defined('APP_ROOT') ? APP_ROOT : __DIR__ . '/..';
+        $testDb  = $root . '/storage/test.db';
+        $prodDb  = $root . '/storage/posterg.db';
+
+        $env = getenv('DB_ENV');
+        if ($env === 'test') return $testDb;
+        if ($env === 'prod') return $prodDb;
+
+        // php -S (dev server) → test DB; everything else (nginx/fpm) → prod DB
+        return php_sapi_name() === 'cli-server' ? $testDb : $prodDb;
     }
 
     /**