reorder fields in OptimizationCache for cleaner dispatches

Since we always dispatch on the optimizer, it makes much more sense
to have this as the first argument (and first type parameter)

Author: SebastianM-C

lib/OptimizationBase/src/cache.jl

@@ -5,16 +5,16 @@ struct AnalysisResults{O, C}
     constraints::C
 end
 
-struct OptimizationCache{F, RC, LB, UB, LC, UC, S, O, P, C, M} <:
+struct OptimizationCache{O, F, RC, LB, UB, LC, UC, S, P, C, M} <:
        SciMLBase.AbstractOptimizationCache
+    opt::O
     f::F
     reinit_cache::RC
     lb::LB
     ub::UB
     lcons::LC
     ucons::UC
     sense::S
-    opt::O
     progress::P
     callback::C
     manifold::M
@@ -46,13 +46,13 @@ function OptimizationCache(prob::SciMLBase.OptimizationProblem, opt;
          prob.f.adtype isa AutoZygote) &&
        (SciMLBase.requireshessian(opt) || SciMLBase.requiresconshess(opt) ||
         SciMLBase.requireslagh(opt))
-        @warn "The selected optimization algorithm requires second order derivatives, but `SecondOrder` ADtype was not provided. 
-        So a `SecondOrder` with $(prob.f.adtype) for both inner and outer will be created, this can be suboptimal and not work in some cases so 
+        @warn "The selected optimization algorithm requires second order derivatives, but `SecondOrder` ADtype was not provided.
+        So a `SecondOrder` with $(prob.f.adtype) for both inner and outer will be created, this can be suboptimal and not work in some cases so
         an explicit `SecondOrder` ADtype is recommended."
     elseif prob.f.adtype isa AutoZygote &&
            (SciMLBase.requiresconshess(opt) || SciMLBase.requireslagh(opt) ||
             SciMLBase.requireshessian(opt))
-        @warn "The selected optimization algorithm requires second order derivatives, but `AutoZygote` ADtype was provided. 
+        @warn "The selected optimization algorithm requires second order derivatives, but `AutoZygote` ADtype was provided.
         So a `SecondOrder` with `AutoZygote` for inner and `AutoForwardDiff` for outer will be created, for choosing another pair
         an explicit `SecondOrder` ADtype is recommended."
     end
@@ -71,9 +71,9 @@ function OptimizationCache(prob::SciMLBase.OptimizationProblem, opt;
         cons_res = nothing
     end
 
-    return OptimizationCache(f, reinit_cache_passedon, prob.lb, prob.ub, prob.lcons,
+    return OptimizationCache(opt, f, reinit_cache_passedon, prob.lb, prob.ub, prob.lcons,
         prob.ucons, prob.sense,
-        opt, progress, callback, manifold, AnalysisResults(obj_res, cons_res),
+        progress, callback, manifold, AnalysisResults(obj_res, cons_res),
         merge((; maxiters, maxtime, abstol, reltol),
             NamedTuple(kwargs)))
 end