fix(iOS): use the module name when rewriting module map paths of spm_dependency pods

[mfazekas]

Summary:

Since #57602, a static pod that declares spm_dependency is built into the shared products dir, and rewrite_aggregate_modulemap_references rewrites the aggregate -fmodule-map-file flags from <Pod>/<Pod>.modulemap to <Pod>.modulemap. CocoaPods names the module map after the pod's module, though (${PODS_CONFIGURATION_BUILD_DIR}/<label>/<product_module_name>.modulemap), and the module name differs from the pod name whenever the pod name isn't a C identifier. For @rnmapbox/maps (pod rnmapbox-maps, module rnmapbox_maps) the flag keeps pointing at rnmapbox-maps/rnmapbox_maps.modulemap, which no longer exists, and the app fails to build on 0.87, 0.88 and current nightlies:

error: module map file '${PODS_CONFIGURATION_BUILD_DIR}/rnmapbox-maps/rnmapbox_maps.modulemap' not found

This takes the module name from the aggregate target's pod targets instead of assuming it equals the pod name.

Changelog:

[IOS] [FIXED] - Fix "module map file not found" for spm_dependency pods whose module name differs from the pod name

Test Plan:

1. Added test_module_map_references_use_the_module_name_of_pods_built_into_the_shared_products_dir to scripts/cocoapods/__tests__/spm-test.rb. It fails before the change (the rnmapbox-maps/rnmapbox_maps.modulemap reference is left as is) and passes after; ruby spm-test.rb: 9 tests, 25 assertions, 0 failures.
2. Created an app with react-native@0.89.0-nightly-20261018-27e77216e and @rnmapbox/maps with its Swift Package Manager opt-in ($RNMapboxMapsSwiftPackageManager = true). Before: pod install writes -fmodule-map-file="${PODS_CONFIGURATION_BUILD_DIR}/rnmapbox-maps/rnmapbox_maps.modulemap" into Pods-App.debug.xcconfig and the build fails with the error above. After applying this patch to the app's node_modules/react-native: the flag is ${PODS_CONFIGURATION_BUILD_DIR}/rnmapbox_maps.modulemap and the Debug build succeeds. With the equivalent path rewrite applied on the library side, the app also launches on the simulator and shows the map, and a Release archive succeeds.