refactor: Reorganize files

HepLean/Tensors/Tree/NodeIdentities/Basic.lean

@@ -250,6 +250,7 @@ lemma prod_add_both {n m : ℕ} {c : Fin n → S.C} {c1 : Fin m → S.C}
 
 -/
 
+/-- The action of a group element can be brought though a scalar multiplication. -/
 lemma smul_action {n : ℕ} {c : Fin n → S.C} (g : S.G) (a : S.k) (t : TensorTree S c) :
     (smul a (action g t)).tensor = (action g (smul a t)).tensor := by
   simp only [smul_tensor, action_tensor, map_smul]