refactor(assemblers): Remove Vec{3} conversions in geometry cache

- Changed 'ξ = Vec{3}(ip.ξ)' to 'ξ = ip.ξ' in two locations
- First occurrence in ∇N_data_tuple computation
- Second occurrence in detJ_w_tuple computation
- No conversions needed since ip.ξ is now already Vec{3}

src/assemblers/geometry_cache.jl

@@ -195,7 +195,7 @@ function create_geometry_cache(
     # Compute gradients and weights at all integration points
     ∇N_data_tuple = ntuple(NIP) do q
         ip = ips[q]
-        ξ = Vec{3}(ip.ξ)
+        ξ = ip.ξ
         w = ip.weight
 
         # Compute Jacobian and physical gradients
@@ -220,7 +220,7 @@ function create_geometry_cache(
     # Compute detJ * weight
     detJ_w_tuple = ntuple(NIP) do q
         ip = ips[q]
-        ξ = Vec{3}(ip.ξ)
+        ξ = ip.ξ
         w = ip.weight
 
         # Recompute Jacobian (could optimize by storing from above)