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/instrument/map/note_entry.cpp

@@ -110,4 +110,4 @@ std::optional<int> parseNoteEntry(const std::string& text) {
     return parseNoteName(s);
 }
 
-}  // namespace reasampler::instrument::map
+}  // namespace reasampler::instrument::map