fix(migration): resolve v1.0.0 password column migration causing login failures (#1059)

Fixes users unable to login after upgrading from v1.0.0 to v1.1.0-dev.16.

The migration was using COALESCE(password_digest, password) which fails in
SQLite when password_digest column doesn't exist in v1.0.0 databases. The
v1.0.0 schema had a 'password' column, not 'password_digest'.

Changes:
- Dynamically detect which password column exists (password vs password_digest)
- Use the correct column in the migration SELECT statement
- Add enhanced trust proxy diagnostics to help debug configuration issues

Tested:
- Created v1.0.0 database with 'password' column
- Verified user login works pre-migration
- Ran migration with fix
- Confirmed password hash preserved and login still works post-migration

backend/app.js

@@ -26,6 +26,8 @@ if (config.trustProxy !== false) {
     console.log(`[Trust Proxy] Disabled (value: false)`);
 }
 
+console.log(`[Trust Proxy] Express setting confirmed:`, app.get('trust proxy'));
+
 // Session store
 const sessionStore = new SequelizeStore({
     db: sequelize,

backend/migrations/20260420000004-make-password-optional.js

@@ -48,6 +48,26 @@ module.exports = {
             );
         `);
 
+        const [columns] = await queryInterface.sequelize.query(
+            'PRAGMA table_info(users);'
+        );
+        const hasPasswordDigest = columns.some(
+            (col) => col.name === 'password_digest'
+        );
+        const hasPassword = columns.some((col) => col.name === 'password');
+
+        const passwordColumn = hasPasswordDigest
+            ? 'password_digest'
+            : hasPassword
+              ? 'password'
+              : null;
+
+        if (!passwordColumn) {
+            throw new Error(
+                'Neither password nor password_digest column found in users table'
+            );
+        }
+
         await queryInterface.sequelize.query(`
             INSERT INTO users_new (
                 id, uid, name, surname, email, password_digest, appearance, language,
@@ -64,7 +84,7 @@ module.exports = {
             )
             SELECT
                 id, uid, name, surname, email,
-                COALESCE(password_digest, password) as password_digest,
+                ${passwordColumn} as password_digest,
                 appearance, language,
                 timezone, first_day_of_week, avatar_image, telegram_bot_token,
                 telegram_chat_id, task_summary_enabled, task_summary_frequency,