Q-W1 code-review follow-ups: restore 104 trailing newlines, relocate reasampler_uid.h to core/wire, drop ext_keys namespaces shim, add slot_map_tests, golden serialize literals for 4 modules, namespaces.h/pragma-once ordering sweep. 60/60 green.

src/core/capture/capture_paths.cpp

@@ -284,4 +284,4 @@ ProjectTransition classifyProjectTransition(bool sameProjectObject,
     return ProjectTransition::NoOp;
 }
 
-} // namespace reasampler::capture
+} // namespace reasampler::capture