UUID: place C++ code in correct namespace

Put the `bUUID` class in the `blender` namespace, instead of the
`blender::bke` namespace.

As a result, some C++ code now correctly uses the C++ class, where
previously it would use the C struct and use implicit casting where
necessary. As a result, support for initializer lists had to be
explicitly coded and in another place an explicit `::bUUID` was
necessary to avoid ambiguity.

source/blender/blenlib/BLI_uuid.h

@@ -68,19 +68,24 @@ bool BLI_uuid_parse_string(bUUID *uuid, const char *buffer) ATTR_NONNULL();
 #ifdef __cplusplus
 }
 
+#  include <initializer_list>
 #  include <ostream>
 
 /** Output the UUID as formatted ASCII string, see #BLI_uuid_format(). */
 std::ostream &operator<<(std::ostream &stream, bUUID uuid);
 
-namespace blender::bke {
+namespace blender {
 
 class bUUID : public ::bUUID {
  public:
   bUUID() = default;
+
   /** Initialise from the bUUID DNA struct. */
   bUUID(const ::bUUID &struct_uuid);
 
+  /** Initialise from 11 integers, 5 for the regular fields and 6 for the `node` array. */
+  bUUID(std::initializer_list<uint> field_values);
+
   /** Initialise by parsing the string; undefined behaviour when the string is invalid. */
   explicit bUUID(const std::string &string_formatted_uuid);
 
@@ -89,6 +94,6 @@ class bUUID : public ::bUUID {
 
 bool operator==(bUUID uuid1, bUUID uuid2);
 
-}  // namespace blender::bke
+}  // namespace blender
 
 #endif