fix: correct malformed shebang in txt2printr.sh

Missing '!' meant the kernel couldn't recognize the interpreter
directive, causing ENOEXEC (errno 8) when executed directly, e.g.
via subprocess.run() from photobooth.py.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

txt2printr.sh

@@ -1,4 +1,4 @@
-#/bin/bash
+#!/bin/bash
 #
 # Sends an ascii-art text file to a parallel port needle/dot-matrix printer.
 #