Preserve old AutoTapir docstring

Author: gdalle

docs/src/index.md

@@ -42,7 +42,6 @@ AutoGTPSA
 AutoMooncake
 AutoReverseDiff
 AutoTracker
-AutoTapir
 AutoZygote
 ```
 
@@ -107,3 +106,9 @@ ADTypes.SymbolicMode
 ```@docs
 ADTypes.Auto
 ```
+
+## Deprecated
+
+```@docs
+AutoTapir
+```

src/dense.jl

@@ -347,6 +347,18 @@ mode(::AutoSymbolics) = SymbolicMode()
 !!! danger
 
     `AutoTapir` is deprecated following a package renaming, please use [`AutoMooncake`](@ref) instead.
+
+Struct used to select the [Tapir.jl](https://github.com/compintell/Tapir.jl) backend for automatic differentiation.
+
+Defined by [ADTypes.jl](https://github.com/SciML/ADTypes.jl).
+
+# Constructors
+
+    AutoTapir(; safe_mode=true)
+
+# Fields
+
+  - `safe_mode::Bool`: whether to run additional checks to catch errors early.
 """
 struct AutoTapir <: AbstractADType
     safe_mode::Bool