fix: mark LuxCore imports as public using @public (#1585)

* Initial plan

* feat: mark LuxCore imports as public using @public

Co-authored-by: avik-pal <[email protected]>

* refactor: move @public declaration for LuxCore imports to end of file

Co-authored-by: avik-pal <[email protected]>

---------

Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: avik-pal <[email protected]>

Author: Copilot

src/Lux.jl

@@ -193,6 +193,20 @@ export LuxOps
 @public Experimental
 @public set_dispatch_doctor_preferences!
 @public Serialization
+@public (
+    initialparameters,
+    initialstates,
+    parameterlength,
+    statelength,
+    outputsize,
+    update_state,
+    trainmode,
+    testmode,
+    setup,
+    apply,
+    replicate,
+    preserves_state_type,
+)
 
 # NNlib.jl reexports
 ## Functional API for common layers. Recommended to use the LuxLib versions