feat(shortcuts): add helper written in egui

This commit adds a simple egui helper application which shows a list of
shortcuts defined in a user's whkdrc file. Parsing AHK files is not
supported.

In addition to listing out shortcuts defined in the whkdrc file, the top
line allows users to add filter a filter to narrow down the list of
commands and key bindings to the ones they are interested in.

A new komorebic command "toggle-shortcuts" has been introduced which
will first attempt to kill "komorebi-shortcuts.exe", and then exit if
the kill signal was successful (ie. a process was closed), or proceed to
open "komorebi-shortcuts.exe" if the kill signal was not successful (ie.
no process was closed, so we should open one).

"komorebi-shortcuts.exe" has been added as a floating application in
lib.rs to allow for users to use the "komorebic move" command to
manipulate its position via their existing keyboard bindings.

wix/main.wxs

@@ -101,6 +101,9 @@
             <Component Id='binary4' Guid='*'>
               <File Id='exe4' Name='komorebi-bar.exe' DiskId='1' Source='$(var.CargoTargetBinDir)\komorebi-bar.exe' KeyPath='yes' />
             </Component>
+            <Component Id='binary5' Guid='*'>
+              <File Id='exe5' Name='komorebi-shortcuts.exe' DiskId='1' Source='$(var.CargoTargetBinDir)\komorebi-shortcuts.exe' KeyPath='yes' />
+            </Component>
           </Directory>
         </Directory>
       </Directory>
@@ -123,6 +126,8 @@
 
       <ComponentRef Id='binary4' />
 
+      <ComponentRef Id='binary5' />
+
       <Feature Id='Environment' Title='PATH Environment Variable' Description='Add the install location of the [ProductName] executable to the PATH system environment variable. This allows the [ProductName] executable to be called from any location.' Level='1' Absent='allow'>
         <ComponentRef Id='Path' />
       </Feature>