Refactor Reconstruction Functions (#570)

### Description
I have relocated the reconstruction functions to all sit within the
HyperbolicSystem class, and tried to minimise code duplication.

### Checklist
- [x] I have added a description (see above).
- [ ] (Not Applicable) I have added a link to any related issues see
(see above).
- [x] I have read the [Contributing
Guide](https://github.com/quokka-astro/quokka/blob/development/CONTRIBUTING.md).
- [ ] (Not Applicable) I have added tests for any new physics that this
PR adds to the code.
- [x] I have tested this PR on my local computer and all tests pass.
- [x] I have manually triggered the GPU tests with the magic comment
`/azp run`.
- [x] I have requested a reviewer for this PR.

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

src/RadhydroSimulation.hpp

@@ -1457,11 +1457,11 @@ void RadhydroSimulation<problem_t>::hydroFluxFunction(amrex::MultiFab const &pri
 						      amrex::MultiFab const &x2Flat, amrex::MultiFab const &x3Flat, const int ng_reconstruct, const int nvars)
 {
 	if (reconstructionOrder_ == 3) {
-		HydroSystem<problem_t>::template ReconstructStatesPPM<DIR>(primVar, leftState, rightState, ng_reconstruct, nvars);
+		HyperbolicSystem<problem_t>::template ReconstructStatesPPM<DIR>(primVar, leftState, rightState, ng_reconstruct, nvars);
 	} else if (reconstructionOrder_ == 2) {
-		HydroSystem<problem_t>::template ReconstructStatesPLM<DIR>(primVar, leftState, rightState, ng_reconstruct, nvars);
+		HyperbolicSystem<problem_t>::template ReconstructStatesPLM<DIR, SlopeLimiter::minmod>(primVar, leftState, rightState, ng_reconstruct, nvars);
 	} else if (reconstructionOrder_ == 1) {
-		HydroSystem<problem_t>::template ReconstructStatesConstant<DIR>(primVar, leftState, rightState, ng_reconstruct, nvars);
+		HyperbolicSystem<problem_t>::template ReconstructStatesConstant<DIR>(primVar, leftState, rightState, ng_reconstruct, nvars);
 	} else {
 		amrex::Abort("Invalid reconstruction order specified!");
 	}
@@ -1832,14 +1832,15 @@ void RadhydroSimulation<problem_t>::fluxFunction(amrex::Array4<const amrex::Real
 
 	if (radiationReconstructionOrder_ == 3) {
 		// mixed interface/cell-centered kernel
-		RadSystem<problem_t>::template ReconstructStatesPPM<DIR>(primVar.array(), x1LeftState.array(), x1RightState.array(), reconstructRange,
-									 x1ReconstructRange, nvars);
+		HyperbolicSystem<problem_t>::template ReconstructStatesPPM<DIR>(primVar.array(), x1LeftState.array(), x1RightState.array(), reconstructRange,
+										x1ReconstructRange, nvars);
 	} else if (radiationReconstructionOrder_ == 2) {
 		// PLM and donor cell are interface-centered kernels
-		RadSystem<problem_t>::template ReconstructStatesPLM<DIR>(primVar.array(), x1LeftState.array(), x1RightState.array(), x1ReconstructRange, nvars);
+		HyperbolicSystem<problem_t>::template ReconstructStatesPLM<DIR, SlopeLimiter::MC>(primVar.array(), x1LeftState.array(), x1RightState.array(),
+												  x1ReconstructRange, nvars);
 	} else if (radiationReconstructionOrder_ == 1) {
-		RadSystem<problem_t>::template ReconstructStatesConstant<DIR>(primVar.array(), x1LeftState.array(), x1RightState.array(), x1ReconstructRange,
-									      nvars);
+		HyperbolicSystem<problem_t>::template ReconstructStatesConstant<DIR>(primVar.array(), x1LeftState.array(), x1RightState.array(),
+										     x1ReconstructRange, nvars);
 	} else {
 		amrex::Abort("Invalid reconstruction order for radiation variables! Aborting...");
 	}