Add monster info popup in battle mode

[jez9999]

Preliminary checks

• [X] I've checked that there aren't other open issues on the same topic.

Describe the problem requiring a solution

The original HOMM2 has a "monster info" option in battle mode, with "None", "Spells only", and "Full". It provides a handy popup on the bottom-right when you mouseover a monster, as well as info on your active unit at the bottom-left. Here's a screenshot of the dialog on Full mode:

For some reason fheroes2 doesn't seem to have this; it should be added.

Describe the possible solution

Add the "monster info" dialog.

Additional info

No response