Canonicalize test units to @safetestset

Convert the independent top-level test units in test/runtests.jl from
plain @testset to @safetestset so each unit runs in its own module
(isolation between tests + world-age safety), matching the canonical
SciML structure.

Each included file is self-contained (carries its own using/import
block). test/test.jl previously relied on the explicit
`using SymbolicAnalysis: propagate_curvature, propagate_sign,
getcurvature, getsign` at the top of runtests.jl leaking into Main;
those names are not exported, so the import is now added directly to
test.jl to keep it self-contained under @safetestset.

Bump test SafeTestsets compat to "0.1, 1" to match the canonical layout.
No test logic, assertions, GROUP dispatch, or which-tests-run changed.

Co-Authored-By: Chris Rackauckas <accounts@chrisrackauckas.com>
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: ChrisRackauckas

test/Project.toml

@@ -22,6 +22,6 @@ Optimization = "5.6.1"
 OptimizationBase = "5.1.3"
 OptimizationManopt = "1.3.2"
 PDMats = "0.11.37"
-SafeTestsets = "0.1.0"
+SafeTestsets = "0.1, 1"
 Symbolics = "7.25.0"
 Zygote = "0.7.10"

test/runtests.jl

@@ -8,26 +8,26 @@ using SymbolicAnalysis:
 
 using SafeTestsets, Test
 
-@testset "DCP" begin
+@safetestset "DCP" begin
     include("test.jl")
 end
 
-@testset "DGCP - SPD Manifold" begin
+@safetestset "DGCP - SPD Manifold" begin
     include("dgp.jl")
 end
 
-@testset "DGCP - Lorentz Manifold" begin
+@safetestset "DGCP - Lorentz Manifold" begin
     include("lorentz.jl")
 end
 
-@testset "Interface Compatibility" begin
+@safetestset "Interface Compatibility" begin
     include("interface_tests.jl")
 end
 
 # AllocCheck tests - run separately to avoid precompilation overhead
 # These tests verify that key operations have minimal allocations
 if get(ENV, "SYMBOLICANALYSIS_TEST_ALLOC", "true") == "true"
-    @testset "Allocation Tests" begin
+    @safetestset "Allocation Tests" begin
         include("alloc_tests.jl")
     end
 end

test/test.jl

@@ -1,4 +1,5 @@
 using SymbolicAnalysis
+using SymbolicAnalysis: propagate_curvature, propagate_sign, getcurvature, getsign
 using Symbolics, SymbolicAnalysis.LogExpFunctions
 using Symbolics: unwrap
 using LinearAlgebra, Test