Log de diagnostic : hôte PostgreSQL ciblé au démarrage

Affiche host/port/db/user à la connexion et un message explicite en cas
d'échec d'authentification persistant, pour identifier immédiatement une
stack déployée avec une ancienne version du compose.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Fkg15RCxNgUys4ru73He2o

server/src/db.js

@@ -11,12 +11,25 @@ export const pool = new pg.Pool({
 export const query = (text, params) => pool.query(text, params);
 
 export async function waitForDb(retries = 30, delayMs = 1000) {
+  console.log(
+    `Connecting to PostgreSQL: host=${config.db.host} port=${config.db.port} ` +
+      `db=${config.db.database} user=${config.db.user}`
+  );
   for (let i = 1; i <= retries; i++) {
     try {
       await pool.query('SELECT 1');
       return;
     } catch (err) {
-      if (i === retries) throw err;
+      if (i === retries) {
+        if (err.code === '28P01') {
+          console.error(
+            'Authentication failed: the sbc_app password in PostgreSQL does not match ' +
+              'PGPASSWORD/APP_DB_PASSWORD. The db-sync service realigns it at every stack ' +
+              'start — make sure it ran against this same database.'
+          );
+        }
+        throw err;
+      }
       await new Promise((r) => setTimeout(r, delayMs));
     }
   }