SSH connection status indicators

- Add Connected bool field to vfs.Entry and RemoteMount
- Track connection status in sshState.connectedHosts
- Show status icon (connected/disconnected) in pane header when browsing remote host
- Async SSH connection test with cancel support for Add Host dialog
- Colored labels and styled help text in SSH dialogs
- Confirmation dialog when deleting manually-added SSH hosts

vendor/golang.org/x/sys/windows/zsyscall_windows.go

@@ -320,6 +320,7 @@ var (
 	procGetVolumePathNamesForVolumeNameW                     = modkernel32.NewProc("GetVolumePathNamesForVolumeNameW")
 	procGetWindowsDirectoryW                                 = modkernel32.NewProc("GetWindowsDirectoryW")
 	procInitializeProcThreadAttributeList                    = modkernel32.NewProc("InitializeProcThreadAttributeList")
+	procIsProcessorFeaturePresent                            = modkernel32.NewProc("IsProcessorFeaturePresent")
 	procIsWow64Process                                       = modkernel32.NewProc("IsWow64Process")
 	procIsWow64Process2                                      = modkernel32.NewProc("IsWow64Process2")
 	procLoadLibraryExW                                       = modkernel32.NewProc("LoadLibraryExW")
@@ -2786,6 +2787,12 @@ func initializeProcThreadAttributeList(attrlist *ProcThreadAttributeList, attrco
 	return
 }
 
+func IsProcessorFeaturePresent(ProcessorFeature uint32) (ret bool) {
+	r0, _, _ := syscall.SyscallN(procIsProcessorFeaturePresent.Addr(), uintptr(ProcessorFeature))
+	ret = r0 != 0
+	return
+}
+
 func IsWow64Process(handle Handle, isWow64 *bool) (err error) {
 	var _p0 uint32
 	if *isWow64 {