chatgui: add local_nick TEXT to peers table DDL, remove ALTER TABLE hacks

tools/chatgui/db/db_manager.cpp

@@ -250,8 +250,6 @@ QMap<quint64, QString> DbManager::getLocalNicknames(const QString& chId) const {
 
 void DbManager::cleanOrphanedPeers(const QString& chId) const {
     if (!m_db) return;
-    QByteArray alt = QString("ALTER TABLE \"%1\" ADD COLUMN local_nick TEXT").arg(peersTableName(chId)).toUtf8();
-    sqlite3_exec(m_db, alt.constData(), nullptr, nullptr, nullptr);
     QString sql = QStringLiteral(
         "DELETE FROM \"%1\" WHERE node_id NOT IN (SELECT node_id FROM nodes)"
     ).arg(peersTableName(chId));