fix(codegen): exclude CASE_OPT_PARAMS from sim generated_decls.fpp

generate_decls_fpp was emitting unconditional declarations for all
sim-target variables including CASE_OPT_PARAMS (recon_type, weno_order,
nb, mapped_weno, viscous, etc.).

m_global_parameters.fpp for simulation contains a manual
#:if MFC_CASE_OPTIMIZATION / #:else block that declares these same
variables — as compile-time constants in case-opt builds and as regular
variables otherwise. The generated include + the manual block created
duplicate declarations, which is a Fortran compile error for every
./mfc.sh build --case-optimization invocation.

Fix: skip CASE_OPT_PARAMS when generating declarations for the sim target.
The manual block handles both the parameter and variable cases.

Author: sbryngelson

toolchain/mfc/params/generators/fortran_gen.py

@@ -100,6 +100,10 @@ def generate_decls_fpp(target: str) -> str:
     for name in _vars_for_target(target):
         if not _is_simple_scalar(name):
             continue
+        # Skip sim case-opt params: declared as compile-time parameters by the
+        # manual #:if MFC_CASE_OPTIMIZATION / #:else block in m_global_parameters.fpp
+        if target == "sim" and name in CASE_OPT_PARAMS:
+            continue
         param = REGISTRY.all_params.get(name)
         if param is None:
             continue