Jamulus iOS crashes on Qt 5.15.19, likely due to stack allocation in main.cpp

**Describe the bug**

Jamulus iOS crashed on my local Qt 5.15.19 build. I was fighting to debug it and then asked GPT 5 SOL. It was extremely fast (and expensive) and pointed out that we allocate too much on the stack causing corruption leading to overwrite something in Qt. I think it does indeed make sense to change this.
Especially the Client object is likely too large.

Also we should remove src/iOS/ios_app_delegate.mm/.h probably as it pollutes some functions in Qt.

Unfortunately, I could not follow the thinking output and cleared the session too quickly - the crash got fixed.

Suggestion: we should use std::unique_ptr's and heap allocation. Maybe this also fixes the Qt6 crashes.

The produced fix actually works.
Proposed diff:
```
diff --git a/src/main.cpp b/src/main.cpp
index a518c2e5..1250d7bf 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -980,17 +980,18 @@ int main ( int argc, char** argv )
#ifndef SERVER_ONLY
if ( bIsClient )
{
- CClient Client ( iPortNumber, iQosNumber, bNoAutoJackConnect, strClientName, bDisableIPv6, bMuteMeInPersonalMix );
+ std::unique_ptr Client (
+ new CClient ( iPortNumber, iQosNumber, bNoAutoJackConnect, strClientName, bDisableIPv6, bMuteMeInPersonalMix ) );

// Create Settings with the client pointer
- CClientSettings Settings ( &Client, strIniFileName );
+ CClientSettings Settings ( Client.get(), strIniFileName );
Settings.Load ( CommandLineOptions );
- Client.SetSettings ( &Settings );
+ Client->SetSettings ( &Settings );

# ifndef NO_JSON_RPC
if ( pRpcServer )
{
- new CClientRpc ( &Client, &Settings, pRpcServer, pRpcServer );
+ new CClientRpc ( Client.get(), &Settings, pRpcServer, pRpcServer );
}
# endif

@@ -1006,7 +1007,7 @@ int main ( int argc, char** argv )

// GUI object
CClientDlg
- ClientDlg ( &Client, &Settings, strConnOnStartupAddress, bShowComplRegConnList, bShowAnalyzerConsole, bMuteStream, nullptr );
+ ClientDlg ( Client.get(), &Settings, strConnOnStartupAddress, bShowComplRegConnList, bShowAnalyzerConsole, bMuteStream, nullptr );

// show dialog
ClientDlg.show();
@@ -1018,8 +1019,8 @@ int main ( int argc, char** argv )
{
if ( !strConnOnStartupAddress.isEmpty() )
{
- Client.SetServerAddr ( strConnOnStartupAddress );
- Client.Start();
+ Client->SetServerAddr ( strConnOnStartupAddress );
+ Client->Start();
}

// only start application without using the GUI
@@ -1033,32 +1034,32 @@ int main ( int argc, char** argv )
{
// Server:
// actual server object
- CServer Server ( iNumServerChannels,
- strLoggingFileName,
- strServerBindIP4,
- strServerBindIP6,
- iPortNumber,
- iQosNumber,
- strDirectoryAddress,
- strServerListFileName,
- strServerInfo,
- strServerPublicIP,
- strServerListFilter,
- strWelcomeMessage,
- strRecordingDirName,
- bDisconnectAllClientsOnQuit,
- bUseDoubleSystemFrameSize,
- bDisableRaw,
- bUseMultithreading,
- bDisableRecording,
- bDelayPan,
- bDisableIPv6,
- eLicenceType );
+ std::unique_ptr Server ( new CServer ( iNumServerChannels,
+ strLoggingFileName,
+ strServerBindIP4,
+ strServerBindIP6,
+ iPortNumber,
+ iQosNumber,
+ strDirectoryAddress,
+ strServerListFileName,
+ strServerInfo,
+ strServerPublicIP,
+ strServerListFilter,
+ strWelcomeMessage,
+ strRecordingDirName,
+ bDisconnectAllClientsOnQuit,
+ bUseDoubleSystemFrameSize,
+ bDisableRaw,
+ bUseMultithreading,
+ bDisableRecording,
+ bDelayPan,
+ bDisableIPv6,
+ eLicenceType ) );

#ifndef NO_JSON_RPC
if ( pRpcServer )
{
- new CServerRpc ( &Server, pRpcServer, pRpcServer );
+ new CServerRpc ( Server.get(), pRpcServer, pRpcServer );
}

#endif
@@ -1066,7 +1067,7 @@ int main ( int argc, char** argv )
if ( bUseGUI )
{
// load settings from init-file (command line options override)
- CServerSettings Settings ( &Server, strIniFileName );
+ CServerSettings Settings ( Server.get(), strIniFileName );
Settings.Load ( CommandLineOptions );

// load translation
@@ -1076,7 +1077,7 @@ int main ( int argc, char** argv )
}

// GUI object for the server
- CServerDlg ServerDlg ( &Server, &Settings, bStartMinimized, nullptr );
+ CServerDlg ServerDlg ( Server.get(), &Settings, bStartMinimized, nullptr );

// show dialog (if not the minimized flag is set)
if ( !bStartMinimized )
@@ -1096,7 +1097,7 @@ int main ( int argc, char** argv )
// strDirectoryAddress is wanted
if ( !strDirectoryAddress.isEmpty() )
{
- Server.SetDirectoryType ( AT_CUSTOM );
+ Server->SetDirectoryType ( AT_CUSTOM );
}

pApp->exec();
```
**To Reproduce**

Compile Qt 5.15.19 on macOS, build Jamulus.
**Expected behavior**

Jamulus does not crash
**Screenshots**

/
**Operating system**

**Version of Jamulus**

**Additional context**

Start in src/main.cpp around the client and server startup paths, then reproduce the crash with a Qt 5.15.19 macOS build. Review the proposed heap-allocation change and the referenced src/iOS/ios_app_delegate.mm/.h files. Done means the iOS build no longer crashes and the affected startup paths still work.

Written by the indexing model from the issue text.