For every file operation I do, I need to do it again via command line to delete or move every single file I already did via dolphin.

So please, let's have the file operations that we do on dolphin also execute a git command to. Let this option be the default wheneven the git plugin is installed on dolphin. Let there be an option to turn off executing git commands for each file operation.

Example:
file delete on dolphin => if git plugin is installed and we are in a git folder => issue "git rm %1" instead.
file move on dolphin => if git plugin is installed and we are in a git folder tree => issue "git mv %1" instead.

file move on dolphin => if git plugin is installed and we are in a git folder A moving another git repo folder B => issue "git rm %1" on folder A, followed by "git add %1" on folder B.

This could be done for other plugins as well, like subversion etc. Maybe DropBox and Google Drive have something similar.