ImagePicker PHPRunner custom edit control

v5 changes:
- Removed the Select button from the popup.
- Clicking a team/card selects it immediately and closes the popup.
- Improved mobile popup layout. On small screens the popup becomes a compact bottom sheet with two-column cards.
- Selected flags remain displayed in a 3:2 landscape ratio.

Files:
- EditImagePicker.php
- EditImagePicker.js
- imagepicker.css
- sample.php
- images/soccer_ball.png

Install as a PHPRunner custom Edit plugin.
