What is AngularJS way to create global keyboard shortcuts?

I would say a more proper way (or "Angular way") would be to add it to a directive. Here's a simple one to get you going (just add keypress-events attribute to <body>):

angular.module('myDirectives', []).directive('keypressEvents', [
  '$document',
  '$rootScope',
  function($document, $rootScope) {
    return {
      restrict: 'A',
      link: function() {
        $document.bind('keypress', function(e) {
          console.log('Got keypress:', e.which);
          $rootScope.$broadcast('keypress', e);
          $rootScope.$broadcast('keypress:' + e.which, e);
        });
      }
    };
  }
]);

In your directive you can then simply do something like this:

module.directive('myDirective', [
  function() {
    return {
      restrict: 'E',
      link: function(scope, el, attrs) {
        scope.keyPressed = 'no press :(';
        // For listening to a keypress event with a specific code
        scope.$on('keypress:13', function(onEvent, keypressEvent) {
          scope.keyPressed = 'Enter';
        });
        // For listening to all keypress events
        scope.$on('keypress', function(onEvent, keypressEvent) {
          if (keypress.which === 120) {
            scope.keyPressed = 'x';
          }
          else {
            scope.keyPressed = 'Keycode: ' + keypressEvent.which;
          }
        });
      },
      template: '<h1>{{keyPressed}}</h1>'
    };
  }
]);

Use $document.bind:

function FooCtrl($scope, $document) {
    ...
    $document.bind("keypress", function(event) {
        console.debug(event)
    });
    ...
}

I can't vouch for it just yet but I've started taking a look at AngularHotkeys.js:

http://chieffancypants.github.io/angular-hotkeys/

Will update with more info once I've got my teeth into it.

Update 1: Oh there's a nuget package: angular-hotkeys

Update 2: actually very easy to use, just set up your binding either in your route or as I'm doing, in your controller:

hotkeys.add('n', 'Create a new Category', $scope.showCreateView);
hotkeys.add('e', 'Edit the selected Category', $scope.showEditView);
hotkeys.add('d', 'Delete the selected Category', $scope.remove);