What changed
Backports #11638 to releases/4.202.x, the release branch for the latest CLI RC (4.202.0-rc.1).
This carries the SwiftPM C-target header fix that prevents directory-style public headers with duplicate basenames from being copied twice into the same framework Headers destination.
Why
The regression can break projects that consume packages shaped like firebase/nanopb, where wrapper public headers and nested module headers share basenames such as pb.h and pb_common.h.
Without this fix, Xcode can fail the build with Multiple commands produce ... nanopb.framework/Headers/pb.h.
Validation
- Cherry-picked cleanly onto
releases/4.202.x.
- Main PR validation is in #11638.
- No further local validation after the backport request.