WATranslate conversation click fix

Replace this server file:

public_html/whatsapp-server-translator/assets/app.js

with the included app.js.

Then hard-refresh WATranslate:
Firefox on Mac: Cmd + Shift + R

Bug fixed:
The old JavaScript generated:
api.php?action=messages%26contact_id%3D123

PHP therefore saw:
action = "messages&contact_id=123"

instead of:
action = "messages"
contact_id = "123"

The patched code now generates:
api.php?action=messages&contact_id=123
