AngularJS code only runs in the html file, not in an external file

There is no need for $(function() {}) because Angular has its own "Document Ready business" (just to simplify to the max :P).

The problem is that Angular can't run its "Document Ready Business" because you are putting Angular stuff inside jQuery's "Document Ready" shorthand and that stops the Angular framework from working properly.

You can read more about this in Angular's documentation

Angular initializes automatically upon DOMContentLoaded event or when the angular.js script is evaluated if at that time document.readyState is set to 'complete'. At this point Angular looks for the ng-app directive which designates your application root.

I think you can see how this conflicts with what you are trying to do.

Also as an additional suggestion go like this:

angular.module('ChgReqApp', []).controller('MainController', function($scope) {
    $scope.ClientInfo = {};
    $scope.ChangeRequests = [];
});

or like this (my preference)

var app = angular.module('ChgReqApp', []);
app.controller('MainController', function($scope) {
    $scope.ClientInfo = {};
    $scope.ChangeRequests = [];
});