fix(cocoapods): dedup prebuilt HEADER_SEARCH_PATHS; keep the FACADE_PODS hint distinct

Two review follow-ups on the deps facades:
- The prebuilt branch of add_rn_third_party_dependencies appended the deps
  Headers search path unconditionally; a second call on the same spec would
  duplicate the entry. Now .uniq, mirroring the from-source branch.
- load_real_spec's method-level rescue also caught the tailored not-found
  raise and re-wrapped it generically, burying the "Update FACADE_PODS"
  hint. The rescue is now scoped to Pod::Specification.from_file only, so
  the two failure messages stay distinct.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: chrfalch

packages/react-native/scripts/cocoapods/rndependencies.rb

@@ -62,7 +62,9 @@ def add_rn_third_party_dependencies(s)
         # Artifact headers are flattened into the pod-local Headers/ by the podspec
         # prepare_command (see __docs__/prebuilt-deps.md).
         header_search_paths << "$(PODS_ROOT)/ReactNativeDependencies/Headers"
-        current_pod_target_xcconfig["HEADER_SEARCH_PATHS"] = header_search_paths
+
+        # uniq so a second call on the same spec can't duplicate entries.
+        current_pod_target_xcconfig["HEADER_SEARCH_PATHS"] = header_search_paths.uniq
     end
 
     s.pod_target_xcconfig = current_pod_target_xcconfig

packages/react-native/scripts/cocoapods/rndeps_facades.rb

@@ -176,9 +176,11 @@ def self.load_real_spec(path, name)
             raise "[RNDepsFacades] Real podspec for facaded pod '#{name}' not found at #{path}. " \
                   "Update FACADE_PODS in rndeps_facades.rb if the podspec moved."
         end
-        Pod::Specification.from_file(path)
-    rescue => e
-        raise "[RNDepsFacades] Failed to read real podspec for facaded pod '#{name}' at #{path}: #{e.message}"
+        begin
+            Pod::Specification.from_file(path)
+        rescue => e
+            raise "[RNDepsFacades] Failed to read real podspec for facaded pod '#{name}' at #{path}: #{e.message}"
+        end
     end
     private_class_method :load_real_spec