Add copy tests to official test suite

- Moved copy tests to test/copy.jl
- Added copy tests to runtests.jl to be run with the test suite
- Removed temporary test files

Author: claude

test_copy.jl renamed to test/copy.jl

@@ -1,5 +1,3 @@
-using Pkg
-Pkg.activate(".")
 using SciMLOperators
 using LinearAlgebra
 using Test
@@ -204,6 +202,31 @@ using Test
         # Check that copy is not affected
         @test L_copy.L.A[1, 1] != 999.0
     end
-end
-
-println("All copy tests passed!")
+    
+    # Test that operators still work correctly after copying
+    @testset "Functionality after copy" begin
+        # MatrixOperator
+        A = rand(5, 5)
+        L = MatrixOperator(A)
+        L_copy = copy(L)
+        v = rand(5)
+        @test L * v ≈ L_copy * v
+        
+        # ScalarOperator
+        α = ScalarOperator(2.0)
+        α_copy = copy(α)
+        @test α * v ≈ α_copy * v
+        
+        # ComposedOperator
+        B = MatrixOperator(rand(5, 5))
+        comp = L ∘ B
+        comp_copy = copy(comp)
+        @test comp * v ≈ comp_copy * v
+        
+        # AffineOperator
+        b = rand(5)
+        aff = AffineOperator(L, B, b)
+        aff_copy = copy(aff)
+        @test aff * v ≈ aff_copy * v
+    end
+end

test/runtests.jl

@@ -28,6 +28,9 @@ end
             @time @safetestset "Zygote.jl" begin
                 include("zygote.jl")
             end
+            @time @safetestset "Copy methods" begin
+                include("copy.jl")
+            end
         elseif GROUP == "All" || GROUP == "Downstream"
             activate_downstream_env()
             @time @safetestset "AllocCheck" begin