I ran out of time to find a solution to this problem. Unfortunately, I only received one answer to this question, and it did not solve my problem. I had to purchase a Zend Studio Perpetual license for Zend Studio 13.6, and now I can use breakpoints, debug my code using Zend Debugger (the competitor of XDebug), and everything works correctly.
I tried as much as I could to fix the problem I experienced with XDebug on both NetBeans and Eclipse, but I ran out of time and I needed to move on. I had to pay $89 for my Zend Studio Perpetual license, which includes free upgrades for one year. I wanted to save money by using Eclipse or NetBeans, but this XDebug issue forced me to move from an open source to a proprietary solution in this case.
Edited on August 29th, 2017:
I finally have XDebug working on Zend Studio. I could not quickly configure Zend Debugger on UniServer Zero XIII, so I did the modifications that I am showing below, to the following file: C:[my path]\UniformServer13_3_2_ZeroXIII\UniServerZ\core\php71\php_production.ini:
[xdebug]
#zend_extension=${US_ROOTF}/core/php71/extensions/php_xdebug.dll
zend_extension="C:\[my path]\UniformServer13_3_2_ZeroXIII\UniServerZ\core\php71\extensions\php_xdebug.dll"
xdebug.remote_autostart=on
xdebug.remote_enable=on
xdebug.remote_host=127.0.0.1
#xdebug.remote_port=9000
xdebug.remote_port=9001
xdebug.remote_handler=dbgp
xdebug.remote_mode=req
xdebug.idekey=default
I changed the port from 9000 to 9001, and used an absolute path with double quotes to the zend_extension to specify where the php_xdebug.dll extension is located. I am not sure if this last step made any difference, or if only changing the port from 9000 to 9001 and then restarting Apache. But at least now I can configure breakpoints to stop the program there and see the values of variables I want to evaluate.