Backport: Bump fmt to 12.1.0 to fix Xcode 26.4 compilation #56225

HSRAKTU wants to merge 3 commits intofacebook:0.83-stablefacebook/react-native:0.83-stablefrom

HSRAKTU:backport-fmt-12.1.0HSRAKTU/react-native:backport-fmt-12.1.0Copy head branch name to clipboard