I have almost updated my app 10 times or more.
But I did not documented my app's build numbers. I have even deleted old archives from Xcode organiser. I checked App Store Connect's version history but it only shows App Versions and not Build Numbers.
Is there any way to know build version for all my app updates and releases?
So far as I know, you just allowed getting the latest version (and build number) of your app in AppStore.
In the Testflight tab, you can watch all the builds that you have upload.
In git?
Don't you have the build history in Archive in Xcode ?
But it is really an important practice to save the complete project at least when you publish on the Appstore. Otherwise, what will you do when a user reports a bug on an older version ?
From the appstoreconnect -> Go under App Review - you can check all the completed tasks and the build number will be under the "Submitted Items"