The MDS file for a TestComplete project appears to store what tabs are currently open in the editor for the project. So, if I have the NameMapping for the project open, a script file, and a keyword ...
This is how test complete already behaves. The open tabs and other such settings are stored in the tcCfgExtender
More info here:
https://support.smartbear.com/testcomplete/docs/working-with/managing-projects/files.html
I would recommend not tracking that file with source control.