RepoConfig

Prerequisites

This config assumes:

• git
  • git config core.ignorecase true is set and the repo is in case-insensitive mode.
    Recommending using git config --global core.ignorecase true to add to global git config.
    Use git config --list --show-origin --show-scope to check your current config.
    Allowing users push file only differ in capitalization will cause all kinds of birrard behaviors on Windows machines.
  • git LFS installed.
• Unity
  • Force text
  • Visible meta files

.gitignore

Since the repo is in case-insensitive mode, all patterns are written without matching capitalization of each character.
A leading slash matches the beginning of the pathname like /Library/ or /Temp/ to only ignore Library/ and Temp/ at project root level.

.gitattribute

Also assuming case-insensitive mode.
Treat everything not text if not overridden by stating * -text at the beginning of .gitattribute. We do not set * binary since we still want to be able to diff .prefab, some .asset and .unity files even though we are not treating them as text files that should go through line ending conversion.
Unity visible meta is LF regardless of created platform so we force .meta as LF by *.meta eol=lf It can fix the issue of .meta constantly changing its line ending on different machines.
Set eol=lf to human authored code, code needs explicit EOL settings to avoid line ending flip-flopping in different editors and polluting git blame. We set EOL to LF even on Windows since we need code as part of input of our own AssetBundle source hashing and they need to have the same file content on both Windows and Mac. Add binary files to LFS, but skip .prefab, .asset (LightingData.asset is certainly binary so added to LFS) and .unity to do text diff. Reading text diff of Unity serialized YAML assets is a very effective way to find changes in Unity assets.

.editorconfig

https://editorconfig.org/
Very basic editor config to force charset and space over tab, it will be followed by most code editors (Notable exception is Visual Studio Code which requires a plugin to support .editorconfig)
Share Visual Studio or Rider config would be a more complete solution if your team can agree on which editor to use.