Raise ModelingToolkitBase floor for array codegen (#482)

* Raise ModelingToolkitBase floor for array codegen

ModelingToolkitBase 1.0 passes symbolic array indices directly to OffsetArrays and errors with the supported SymbolicUtils floor. Version 1.1 uses the stable-index API and is the first compatible release.

Co-Authored-By: Chris Rackauckas <accounts@chrisrackauckas.com>

* Test symbolic array state codegen

Add a focused regression that compiles a StateSpace block with array states and constructs its ODEProblem under downgraded dependencies.

Co-Authored-By: Chris Rackauckas <accounts@chrisrackauckas.com>

* Delete test/array_state_codegen.jl

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Co-authored-by: ChrisRackauckas-Claude <accounts@chrisrackauckas.com>

Author: ChrisRackauckas-Claude

Project.toml

@@ -22,7 +22,7 @@ DiffEqBase = "6.190, 7"
 ForwardDiff = "0.10, 1"
 LinearAlgebra = "1.10"
 ModelingToolkit = "11"
-ModelingToolkitBase = "1"
+ModelingToolkitBase = "1.1"
 OrdinaryDiffEq = "6, 7"
 OrdinaryDiffEqBDF = "1, 2"
 OrdinaryDiffEqDefault = "1, 2"