dispose static method
Dispose all accounts
Implementation
static Future<void> dispose() async {
try {
for (final accountId in _sipHelpers.keys.toList()) {
await unregisterAccount(accountId);
}
_shownCallIds.clear();
debugPrint('✅ Multi-SIP Service disposed');
} catch (e, stackTrace) {
_printException('Dispose', e, stackTrace);
}
}