fix(yes): restore SIGPIPE to default handler

Fixes broken pipe handling by unconditionally restoring SIGPIPE to SIG_DFL
at program startup, following the established pattern used in cat, tr, and
tail utilities.

This ensures the process properly terminates with exit code 141 when writing
to closed pipes, rather than ignoring SIGPIPE as Rust does by default.

Related to issue #7252 and PR #9560.

Author: naoNao89

src/uu/stty/src/stty.rs

@@ -997,7 +997,7 @@ fn apply_char_mapping(termios: &mut Termios, mapping: &(S, u8)) {
 ///
 /// The state array contains:
 /// - `state[0]`: input flags
-/// - `state[1]`: output flags  
+/// - `state[1]`: output flags
 /// - `state[2]`: control flags
 /// - `state[3]`: local flags
 /// - `state[4..]`: control characters (optional)

tests/by-util/test_ls.rs

@@ -6498,7 +6498,7 @@ fn test_f_overrides_sort_flags() {
 
     // Create files with different sizes for predictable sort order
     at.write("small.txt", "a"); // 1 byte
-    at.write("medium.txt", "bb"); // 2 bytes  
+    at.write("medium.txt", "bb"); // 2 bytes
     at.write("large.txt", "ccc"); // 3 bytes
 
     // Get baseline outputs (include -a to match -f behavior which shows all files)