feat: wait up to 10s for a late MONTAUKROOT, retry USB enumeration after a port reset, recover halted EP0/bulk endpoints, MSC card reader settle

kernel/src/Boot/Main.cpp

@@ -32,6 +32,7 @@
 #include <Arch/Cpu.hpp>
 #include <Arch/Platform.hpp>
 #include <Fs/Boot.hpp>
+#include <Fs/Vfs.hpp>
 #include <Sched/Scheduler.hpp>
 #include <Ipc/Ipc.hpp>
 #include <Api/Syscall.hpp>
@@ -178,6 +179,11 @@ extern "C" void kmain() {
 
     Arch::LateInitialize();
 
+    // Without a root nothing can start; say so instead of idling silently.
+    if (!Fs::Vfs::IsDriveRegistered(0)) {
+        Panic("No root filesystem (0:/): cannot start 0:/os/init.elf", nullptr);
+    }
+
     Kt::SuppressKernelLog();
     Sched::Spawn("0:/os/init.elf");