refactor: Update AllocatedPoint type specifications in circuits and g…

…adgets (#299)

- Change the parameter of `AllocatedPoint` from an `Engine` to the more minimal setup of a `Group`
- Ensure no changes are made to the operating logic of the code, only type specification has been updated.

Downstream changes:
- Modify data type of `W` and `E` fields in structures `AllocatedR1CSInstance` and `AllocatedRelaxedR1CSInstance` to `AllocatedPoint<E::GE>` along with the type of `T` parameter in `fold_with_r1cs`.
- Update `conditionally_select_point` function in `gadgets/r1cs.rs` to use a generic parameter `G` that inherits from `Group` instead of `E` from `Engine`.
- Update method signatures in `NovaAugmentedCircuit` and `SuperNovaAugmentedCircuit` to accommodate changes in the underlying type of `AllocatedPoint` from `E` to `E::GE`.

src/circuit.rs

@@ -119,7 +119,7 @@ impl<'a, E: Engine, SC: StepCircuit<E::Base>> NovaAugmentedCircuit<'a, E, SC> {
       Vec<AllocatedNum<E::Base>>,
       AllocatedRelaxedR1CSInstance<E>,
       AllocatedR1CSInstance<E>,
-      AllocatedPoint<E>,
+      AllocatedPoint<E::GE>,
     ),
     SynthesisError,
   > {
@@ -214,7 +214,7 @@ impl<'a, E: Engine, SC: StepCircuit<E::Base>> NovaAugmentedCircuit<'a, E, SC> {
     z_i: &[AllocatedNum<E::Base>],
     U: &AllocatedRelaxedR1CSInstance<E>,
     u: &AllocatedR1CSInstance<E>,
-    T: &AllocatedPoint<E>,
+    T: &AllocatedPoint<E::GE>,
     arity: usize,
   ) -> Result<(AllocatedRelaxedR1CSInstance<E>, AllocatedBit), SynthesisError> {
     // Check that u.x[0] = Hash(params, U, i, z0, zi)