chore(macros): reorganize module hierarchy in mingling_macros

Restructure flat module layout into logical directories (attr/, derive/,
func/, systems/, extensions/, utils.rs). Tighten internal function
visibility to pub(crate). All public API signatures remain unchanged.

1 files changed, 2 insertions, 0 deletions

diff --git a/mingling_macros/src/derive.rs b/mingling_macros/src/derive.rs
new file mode 100644
index 0000000..ffa405b
--- /dev/null
+++ b/mingling_macros/src/derive.rs
@@ -0,0 +1,2 @@
+pub(crate) mod enum_tag;
+pub(crate) mod grouped;