feat: add tclsh, wish, and expect shebang detection for Tcl syntax

Add first_line_match to the Tcl syntax definition via a patch file,
enabling automatic Tcl highlighting for scripts with tclsh, wish,
or expect shebangs.

Fixes #3513

CHANGELOG.md

@@ -9,6 +9,7 @@
 ## Features
 
 - Preserve `--diff` change markers and snip separators when `--plain` is set. Closes #3630, see #3643 (@mvanhorn)
+- Add shebang-based detection for Tcl (`tclsh`, `wish`) and Expect (`expect`) scripts, see #3513 (@mvanhorn)
 - Added support for `hidden_file_extensions` from `.sublime-syntax` files, see #3613 (@Matei02355)
 - Add word wrapping mode via `--wrap=word`, see #3597 (@veeceey)
 - Support configuring `--terminal-width` via `BAT_WIDTH`, see #3679 (@officialasishkumar)

assets/patches/Tcl.sublime-syntax.patch

@@ -0,0 +1,12 @@
+diff --git syntaxes/01_Packages/TCL/Tcl.sublime-syntax syntaxes/01_Packages/TCL/Tcl.sublime-syntax
+index 1234567..abcdefg 100644
+--- syntaxes/01_Packages/TCL/Tcl.sublime-syntax
++++ syntaxes/01_Packages/TCL/Tcl.sublime-syntax
+@@ -3,6 +3,7 @@
+ # http://www.sublimetext.com/docs/3/syntax.html
+ name: Tcl
+ file_extensions:
+   - tcl
++first_line_match: ^\#!.*\b(tclsh|wish|expect)\b
+ scope: source.tcl
+ variables: