Optimize multiple places for rendering

[ihhub]

• all event loops during battle animations did not check whether it is allowed to do rendering within handle event loop
• custom delays were not reset properly causing slight delays in first frame to be rendered. Video playback was affected the most
• avoid excessive rendering for multiple windows. Render only the area which was changed
• add todo comments for the future changes
• some animations during battle did not play the last frame like monster animation, hero's animation and hero's flag animation
• small code cleanup

[ihhub]

Hi @Districh-ru , I would like to see your opinion about these changes, especially about animation of monsters, flags and heroes. Some monsters have become more smooth in animation but some like wolves not. It would be great if you can verify that I didn't break anything in your past efforts for animation.

[sonarqubecloud[bot]]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
4 Code Smells

0.0% Coverage
0.0% Duplication