fix(output): strip stderr color on a pipe where std's eprint! kept it

src/commands/config/update.rs

@@ -15,8 +15,8 @@ use worktrunk::config::{
 };
 use worktrunk::git::Repository;
 use worktrunk::styling::{
-    eprintln, format_bash_with_gutter, hint_message, info_message, print, println, success_message,
-    suggest_command_in_dir,
+    eprint, eprintln, format_bash_with_gutter, hint_message, info_message, print, println,
+    success_message, suggest_command_in_dir,
 };
 
 use crate::output::prompt::{PromptResponse, prompt_yes_no_preview};

src/config/deprecation.rs

@@ -45,7 +45,7 @@ use shell_escape::unix::escape;
 use crate::config::WorktrunkConfig;
 use crate::shell_exec::Cmd;
 use crate::styling::{
-    eprintln, format_with_gutter, hint_message, info_message, suggest_command_in_dir,
+    eprint, eprintln, format_with_gutter, hint_message, info_message, suggest_command_in_dir,
     warning_message,
 };
 

src/output/prompt.rs

@@ -3,7 +3,7 @@
 use std::io::{self, Write};
 
 use color_print::cformat;
-use worktrunk::styling::PROMPT_SYMBOL;
+use worktrunk::styling::{PROMPT_SYMBOL, eprint, eprintln};
 
 /// Response from a `[y/N/?]` prompt.
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
@@ -42,7 +42,7 @@ pub fn prompt_yes_no_preview(
     show_preview: impl Fn(),
 ) -> io::Result<PromptResponse> {
     // Blank line before first prompt for visual separation
-    worktrunk::styling::eprintln!();
+    eprintln!();
 
     loop {
         eprint!(

tests/integration_tests/output_system_guard.rs

@@ -240,3 +240,41 @@ fn test_stdout_surfaces_survive_a_closed_consumer(repo: TestRepo) {
         );
     }
 }
+
+/// Narration on stderr strips its color when stderr isn't a terminal.
+///
+/// The stdout rule above has a stderr counterpart, and it is the same mistake:
+/// `worktrunk::styling`'s `eprint!` is anstream's and strips ANSI off a
+/// non-tty, std's prelude macro of the same name keeps it. A file that
+/// imported `eprintln` from `styling` but not `eprint` got one of each, so a
+/// deprecation warning and the hint printed directly beneath it disagreed
+/// about whether `wt list 2>log` should carry escapes.
+///
+/// The suite's own `CLICOLOR_FORCE=1` is what hides this — it forces color on
+/// both printers, so every snapshot agrees no matter which macro is in scope.
+/// This test clears it and sets `NO_COLOR`, which only anstream honors.
+///
+/// The trigger is a deprecated `[ci]` block, whose warning is emitted by the
+/// pre-deserialization deprecation pass on every command that loads config.
+#[rstest]
+fn test_stderr_narration_strips_ansi_when_piped(repo: TestRepo) {
+    repo.write_project_config("[ci]\nplatform = \"github\"\n");
+
+    let output = repo
+        .wt_command()
+        .arg("list")
+        .env_remove("CLICOLOR_FORCE")
+        .env("NO_COLOR", "1")
+        .output()
+        .expect("failed to run wt list");
+
+    let stderr = String::from_utf8_lossy(&output.stderr);
+    assert!(
+        stderr.contains("deprecated"),
+        "expected the [ci] deprecation warning on stderr; got: {stderr:?}"
+    );
+    assert!(
+        !stderr.contains('\x1b'),
+        "wt narration redirected to a file must not contain ANSI escapes; got: {stderr:?}"
+    );
+}