Fix show for MethodList when methods are from another module

When a type is defined in one module but its methods are defined
elsewhere, `show_method_table` errors due to an incorrect lookup of the
defining module used to determine colors for printing. In particular,
the code had been assuming that the type is defined in the module in
which its constructor's first method (in the sense of
`first(methods())`) is defined, which isn't always true.

To fix this, we can look through the available methods and choose the
first in which the type is defined in the method's module, falling back
to the method table's module otherwise.

Fixes #49382
Fixes #49403
Fixes #52043

base/methodshow.jl

@@ -301,7 +301,8 @@ function show_method_table(io::IO, ms::MethodList, max::Int=-1, header::Bool=tru
     last_shown_line_infos === nothing || empty!(last_shown_line_infos)
 
     modul = if mt === _TYPE_NAME.mt && length(ms) > 0 # type constructor
-            which(ms.ms[1].module, ms.ms[1].name)
+            i = findfirst(m -> isdefined(m.module, m.name), ms.ms)
+            i === nothing ? mt.module : which(ms.ms[i].module, ms.ms[i].name)
         else
             mt.module
         end

test/show.jl

@@ -2652,3 +2652,10 @@ let buf = IOBuffer()
     Base.show_tuple_as_call(buf, Symbol(""), Tuple{Function,Any})
     @test String(take!(buf)) == "(::Function)(::Any)"
 end
+
+module Issue49382
+    abstract type Type49382 end
+end
+using .Issue49382
+(::Type{Issue49382.Type49382})() = 1
+@test sprint(show, methods(Issue49382.Type49382)) isa String