Core/VideoBackends: Use range-based loops

New rules:
`InsertNewlineAtEOF: true`
`RemoveSemicolon: true`
`RequiresClausePosition: WithPreceding`

find ./Source/ -name '*.cpp' -o -name '*.h' | xargs clang-format-19 -i

My personal fork requires minimum iOS 14, so this is not required.

The minimum macOS (and minimum iOS on my personal fork) are enough to allow MSL 2.3 usage without availability checks.