test: add shebang regression tests and move changelog to Syntaxes section

Add extensionless regression test files for tclsh, wish, and expect
shebangs so syntect bumps don't silently break first-line detection.
Move changelog entry from Features to Syntaxes per reviewer suggestion.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

CHANGELOG.md

@@ -10,10 +10,9 @@
 
 <<<<<<< HEAD
 - 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)
-=======
 - Add shebang-based detection for Tcl (`tclsh`, `wish`) and Expect (`expect`) scripts, see #3647 (@mvanhorn)
->>>>>>> 785fff9 (fix: reference PR number in changelog entry)
+=======
+>>>>>>> 29c913f (test: add shebang regression tests and move changelog to Syntaxes section)
 - 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)
@@ -50,6 +49,7 @@
 
 ## Syntaxes
 
+- Add shebang-based detection for Tcl (`tclsh`, `wish`) and Expect (`expect`) scripts, see #3647 (@mvanhorn)
 - Change the URL of Zig submodule from GitHub to Codeberg, see #3519 (@sorairolake)
 - Don't color strings inside CSV files, to make it easier to tell which column they belong to, see #3521 (@keith-hall)
 - Add syntax highlighting support for COBOL, see #3584 (@adukhan99)