Fix: Use Enzyme instead of non-existent EnzymeRules package

EnzymeRules is not a standalone package - it's part of Enzyme.
Correct extension setup:
- import Enzyme: EnzymeRules (not import EnzymeRules)
- Enzyme as weakdep (not EnzymeRules)
- SciMLBaseEnzymeExt = "Enzyme" (not "EnzymeRules")

This fixes the AbstractSensitivityAlgorithm inactive_type rule for
SciMLSensitivity.jl#1225 where Enzyme fails when sensealg is passed
to ODEProblem constructor.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: ChrisRackauckas

Project.toml

@@ -37,7 +37,7 @@ SymbolicIndexingInterface = "2efcf032-c050-4f8e-a9bb-153293bab1f5"
 ChainRules = "082447d4-558c-5d27-93f4-14fc19e9eca2"
 ChainRulesCore = "d360d2e6-b24c-11e9-a2a3-2a2ae2dbcce4"
 Distributions = "31c24e10-a181-5473-b8eb-7969acd0382f"
-EnzymeRules = "b2b7a20a-8ddc-4497-9a0a-d49b80ff0020"
+Enzyme = "7da242da-08ed-463a-9acd-ee780be4f1d9"
 ForwardDiff = "f6369f11-7733-5829-9624-2563aa707210"
 MLStyle = "d8e11817-5142-5d16-987a-aa16d5891078"
 Makie = "ee78f7c6-11fb-53f2-987a-cfe4a2b5a57a"
@@ -55,7 +55,7 @@ Zygote = "e88e6eb3-aa80-5325-afca-941959d7151f"
 [extensions]
 SciMLBaseChainRulesCoreExt = "ChainRulesCore"
 SciMLBaseDistributionsExt = "Distributions"
-SciMLBaseEnzymeExt = "EnzymeRules"
+SciMLBaseEnzymeExt = "Enzyme"
 SciMLBaseForwardDiffExt = "ForwardDiff"
 SciMLBaseMLStyleExt = "MLStyle"
 SciMLBaseMakieExt = "Makie"
@@ -82,7 +82,7 @@ ConstructionBase = "1.5"
 Distributed = "1.10"
 Distributions = "0.25"
 DocStringExtensions = "0.9"
-EnzymeRules = "0.1"
+Enzyme = "0.13"
 EnumX = "1"
 ForwardDiff = "0.10.36, 1"
 FunctionWrappersWrappers = "0.1.3"

ext/SciMLBaseEnzymeExt.jl

@@ -1,7 +1,7 @@
 module SciMLBaseEnzymeExt
 
 using SciMLBase
-import EnzymeRules
+import Enzyme: EnzymeRules
 
 # Enzyme rules for SciMLBase abstract types
 #