Add IOP, audio, pad, fio changes, VAG handling, and call-stack logger (#76)

- Add IOP with RPC handling (handleRPC, LibSd SID) and init/reset using RDRAM
- Add IOP audio layer for LibSd RPC (handleLibSdRpc)
- Add PS2AudioBackend with VAG decode, onVagTransfer/onSoundCommand, raylib playback
- Add PSPadBackend with readState and raylib input
- Add IOP RAM mapping in Memory (getIOPRAM) for EE↔IOP access
- Add fio syscalls: fioOpen, fioRead, fioWrite, fioClose, fioLseek, fioMkdir
- Add VAG accumulation for fio reads (multi-chunk VagAccumEntry)
- Add ps2_log.h call-stack logger (tab-indented, Debug only, ps2_log.txt next to exe)
- Code generator: emit ps2_log include and PS_LOG_ENTRY for full functions
- Recompiler: emit ps2_log include and PS_LOG_ENTRY for stubs
- Runtime: print "[PS2 LOG] Logs saved at <path>" on exit (Debug only)

ps2xRuntime/src/lib/ps2_runtime.cpp

@@ -296,8 +296,13 @@ bool PS2Runtime::initialize(const char *title)
         return false;
     }
 
+    m_iop.init(m_memory.getRDRAM());
+    m_iop.reset();
+
     SetConfigFlags(FLAG_WINDOW_RESIZABLE);
     InitWindow(FB_WIDTH, FB_HEIGHT, title);
+    InitAudioDevice();
+    m_audioBackend.setAudioReady(IsAudioDeviceReady());
     SetTargetFPS(60);
 
     return true;