Find{TCL,Tclsh,TclStub,Wish}: Add support for Tcl/Tk 9.0 & 9.1

Tcl/Tk 9.0.0 was released[1] in 2024, and is already up to version
9.0.4 (just released 2026-07-26).

Tcl/Tk 9.1 is currently nearing beta,[2] and will likely release soon.

Since it's still possible to have both of these libraries installed
without Tclsh or Wish (making version detection via those tools
unviable), add 9.0 and 9.1 variants to the explicit library/include
path and file matches performed by FindTCL.

Also add 9.0 and 9.1 patterns to the tool detections in FindTclsh,
FindTclStub, and FindWish.

[1]: https://sourceforge.net/projects/tcl/files/Tcl/9.0.0/
[2]: https://sourceforge.net/projects/tcl/files/Tcl/9.1b0/

Modules/FindTCL.cmake

@@ -116,6 +116,10 @@ set(TCLTK_POSSIBLE_LIB_PATHS
 )
 
 set(TCLTK_POSSIBLE_LIB_PATH_SUFFIXES
+  lib/tcl/tcl9.1
+  lib/tcl/tk9.1
+  lib/tcl/tcl9.0
+  lib/tcl/tk9.0
   lib/tcl/tcl8.6
   lib/tcl/tk8.6
   lib/tcl/tcl8.5
@@ -141,6 +145,8 @@ find_library(TCL_LIBRARY
   NAMES
   tcl
   tcl${TCL_LIBRARY_VERSION} tcl${TCL_TCLSH_VERSION} tcl${TK_WISH_VERSION}
+  tcl91 tcl9.1 tcl91t tcl9.1t
+  tcl90 tcl9.0 tcl90t tcl9.0t
   tcl86 tcl8.6 tcl86t tcl8.6t
   tcl85 tcl8.5
   tcl84 tcl8.4
@@ -155,6 +161,8 @@ find_library(TK_LIBRARY
   NAMES
   tk
   tk${TK_LIBRARY_VERSION} tk${TCL_TCLSH_VERSION} tk${TK_WISH_VERSION}
+  tk91 tk9.1 tk91t tk9.1t
+  tk90 tk9.0 tk90t tk9.0t
   tk86 tk8.6 tk86t tk8.6t
   tk85 tk8.5
   tk84 tk8.4
@@ -201,6 +209,10 @@ set(TCLTK_POSSIBLE_INCLUDE_PATHS
 set(TCLTK_POSSIBLE_INCLUDE_PATH_SUFFIXES
   include/tcl${TK_LIBRARY_VERSION}
   include/tcl${TCL_LIBRARY_VERSION}
+  include/tcl9.1
+  include/tk9.1
+  include/tcl9.0
+  include/tk9.0
   include/tcl8.6
   include/tk8.6
   include/tcl8.5

Modules/FindTclStub.cmake

@@ -119,6 +119,8 @@ find_library(TCL_STUB_LIBRARY
   NAMES
   tclstub
   tclstub${TK_LIBRARY_VERSION} tclstub${TCL_TCLSH_VERSION} tclstub${TK_WISH_VERSION}
+  tclstub91 tclstub9.1
+  tclstub90 tclstub9.0
   tclstub86 tclstub8.6
   tclstub85 tclstub8.5
   tclstub84 tclstub8.4
@@ -132,6 +134,8 @@ find_library(TK_STUB_LIBRARY
   NAMES
   tkstub
   tkstub${TCL_LIBRARY_VERSION} tkstub${TCL_TCLSH_VERSION} tkstub${TK_WISH_VERSION}
+  tkstub91 tkstub9.1
+  tkstub90 tkstub9.0
   tkstub86 tkstub8.6
   tkstub85 tkstub8.5
   tkstub84 tkstub8.4
@@ -145,6 +149,8 @@ find_library(TTK_STUB_LIBRARY
   NAMES
   ttkstub
   ttkstub${TCL_LIBRARY_VERSION} ttkstub${TCL_TCLSH_VERSION} ttkstub${TK_WISH_VERSION}
+  ttkstub91 ttkstub9.1
+  ttkstub90 ttkstub9.0
   ttkstub86 ttkstub8.6
   ttkstub85 ttkstub8.5
   PATHS ${TCLTK_POSSIBLE_LIB_PATHS}

Modules/FindTclsh.cmake

@@ -114,6 +114,8 @@ endif()
 set(TCL_TCLSH_NAMES
   tclsh
   tclsh${TCL_LIBRARY_VERSION} tclsh${TK_LIBRARY_VERSION} tclsh${TK_WISH_VERSION}
+  tclsh91 tclsh9.1
+  tclsh90 tclsh9.0
   tclsh86 tclsh8.6
   tclsh85 tclsh8.5
   tclsh84 tclsh8.4

Modules/FindWish.cmake

@@ -90,6 +90,8 @@ endif()
 set(TK_WISH_NAMES
   wish
   wish${TCL_LIBRARY_VERSION} wish${TK_LIBRARY_VERSION} wish${TCL_TCLSH_VERSION}
+  wish91 wish9.1
+  wish90 wish9.0
   wish86 wish8.6
   wish85 wish8.5
   wish84 wish8.4