fix(iOS): make jsinspector-modern tracing state types move-only for Swift C++ interop

TraceRecordingState and HostTracingProfile hold std::vector<> of
move-only types (RuntimeSamplingProfile, FrameTimingSequence). Their
implicit copy constructors are declared but ill-formed on instantiation.
Plain C++ never instantiates them, but a Swift target using
-cxx-interoperability-mode=default (any Nitro-based library) imports
these types via the prebuilt clang modules and its generated bridging
uses them as copyable Swift values, forcing instantiation of the
ill-formed copy ctor — a hard error on Xcode 26.3 that kills every Swift
file in the consumer (e.g. react-native-unistyles in nightly-tests).

Declare the types explicitly move-only. Swift then imports them as
non-copyable; it is also more correct C++ (these types were never
copyable). HostTracingProfile is no longer an aggregate, so its one
designated-initializer site is converted to member assignment.

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

Author: chrfalch

packages/react-native/ReactCommon/jsinspector-modern/HostTargetTraceRecording.cpp

@@ -64,13 +64,16 @@ tracing::HostTracingProfile HostTargetTraceRecording::stop() {
   auto startTime = *startTime_;
   startTime_.reset();
 
-  return tracing::HostTracingProfile{
-      .processId = oscompat::getCurrentProcessId(),
-      .startTime = startTime,
-      .frameTimings = frameTimings_.pruneExpiredAndExtract(),
-      .instanceTracingProfiles = std::move(state.instanceTracingProfiles),
-      .runtimeSamplingProfiles = std::move(state.runtimeSamplingProfiles),
-  };
+  // Member-wise assignment instead of designated initializers:
+  // HostTracingProfile declares its special members (move-only) and is no
+  // longer an aggregate.
+  tracing::HostTracingProfile profile;
+  profile.processId = oscompat::getCurrentProcessId();
+  profile.startTime = startTime;
+  profile.frameTimings = frameTimings_.pruneExpiredAndExtract();
+  profile.instanceTracingProfiles = std::move(state.instanceTracingProfiles);
+  profile.runtimeSamplingProfiles = std::move(state.runtimeSamplingProfiles);
+  return profile;
 }
 
 void HostTargetTraceRecording::recordFrameTimings(

packages/react-native/ReactCommon/jsinspector-modern/tracing/HostTracingProfile.h

@@ -23,6 +23,18 @@ namespace facebook::react::jsinspector_modern::tracing {
  * messages.
  */
 struct HostTracingProfile {
+  HostTracingProfile() = default;
+
+  // Explicitly move-only: FrameTimingSequence and RuntimeSamplingProfile are
+  // not copyable, so the implicit copy constructor is ill-formed the moment it
+  // is instantiated. Plain C++ never instantiates it, but Swift's C++ interop
+  // does when these headers are reached from an imported module, turning it
+  // into a hard compile error (Xcode 26.3).
+  HostTracingProfile(const HostTracingProfile &) = delete;
+  HostTracingProfile &operator=(const HostTracingProfile &) = delete;
+  HostTracingProfile(HostTracingProfile &&) = default;
+  HostTracingProfile &operator=(HostTracingProfile &&) = default;
+
   // The ID of the OS-level process that this Trace Recording is associated
   // with.
   ProcessId processId;

packages/react-native/ReactCommon/jsinspector-modern/tracing/TraceRecordingState.h

@@ -31,6 +31,16 @@ struct TraceRecordingState {
   {
   }
 
+  // Explicitly move-only: RuntimeSamplingProfile is not copyable, so the
+  // implicit copy constructor is ill-formed the moment it is instantiated.
+  // Plain C++ never instantiates it, but Swift's C++ interop (ClangImporter)
+  // does when a consumer imports these headers as part of a module, turning
+  // it into a hard compile error (Xcode 26.3).
+  TraceRecordingState(const TraceRecordingState &) = delete;
+  TraceRecordingState &operator=(const TraceRecordingState &) = delete;
+  TraceRecordingState(TraceRecordingState &&) = default;
+  TraceRecordingState &operator=(TraceRecordingState &&) = default;
+
   // The mode of this Trace Recording.
   tracing::Mode mode;