Stop identifying Apple Terminal from TERM_SESSION_ID (#53438)

## Why

`TERM_SESSION_ID` is not specific to Apple Terminal. Treating it as an Apple Terminal identifier can mask Windows Terminal detection and the `TERM` fallback.

## What changed

Remove the `TERM_SESSION_ID` detection heuristic. Apple Terminal remains detectable through `TERM_PROGRAM=Apple_Terminal`.

## Testing

Update tests to cover Windows Terminal detection and the `TERM` fallback when `TERM_SESSION_ID` is present, and Apple Terminal detection with its version and user-agent token.

GitOrigin-RevId: 27db11cb7bcca8f94888f9e21a6cdfcf31561b1b

codex-rs/terminal-detection/src/lib.rs

@@ -248,7 +248,8 @@ pub fn terminal_info() -> TerminalInfo {
 /// - `TERM_PROGRAM` (plus `TERM_PROGRAM_VERSION`) drives the detected terminal name,
 ///   except when it identifies tmux rather than the underlying terminal.
 ///   This means `TERM_PROGRAM` can mask later probes (for example `WT_SESSION`).
-/// - Next, terminal-specific variables (WEZTERM, iTerm2, Apple Terminal, kitty, etc.) are checked.
+/// - Next, terminal-specific variables (WEZTERM, iTerm2, kitty, etc.) are checked.
+///   `TERM_SESSION_ID` is not terminal-specific and cannot identify Apple Terminal.
 /// - Finally, `TERM` is used as the capability fallback.
 fn detect_terminal_info_from_env(env: &dyn Environment) -> TerminalInfo {
     let multiplexer = detect_multiplexer(env);
@@ -274,14 +275,6 @@ fn detect_terminal_info_from_env(env: &dyn Environment) -> TerminalInfo {
         return TerminalInfo::from_name(TerminalName::Iterm2, /*version*/ None, multiplexer);
     }
 
-    if env.has("TERM_SESSION_ID") {
-        return TerminalInfo::from_name(
-            TerminalName::AppleTerminal,
-            /*version*/ None,
-            multiplexer,
-        );
-    }
-
     if env.has("KITTY_WINDOW_ID")
         || env
             .var("TERM")

codex-rs/terminal-detection/src/terminal_tests.rs

@@ -153,14 +153,17 @@ fn detects_iterm2() {
 
 #[test]
 fn detects_apple_terminal() {
-    let env = FakeEnvironment::new().with_var("TERM_PROGRAM", "Apple_Terminal");
+    let env = FakeEnvironment::new()
+        .with_var("TERM_PROGRAM", "Apple_Terminal")
+        .with_var("TERM_PROGRAM_VERSION", "455")
+        .with_var("TERM_SESSION_ID", "A1B2C3");
     let terminal = detect_terminal_info_from_env(&env);
     assert_eq!(
         terminal,
         terminal_info(
             TerminalName::AppleTerminal,
             Some("Apple_Terminal"),
-            /*version*/ None,
+            Some("455"),
             /*term*/ None,
             /*multiplexer*/ None,
         ),
@@ -168,28 +171,9 @@ fn detects_apple_terminal() {
     );
     assert_eq!(
         terminal.user_agent_token(),
-        "Apple_Terminal",
+        "Apple_Terminal/455",
         "apple_term_program_user_agent"
     );
-
-    let env = FakeEnvironment::new().with_var("TERM_SESSION_ID", "A1B2C3");
-    let terminal = detect_terminal_info_from_env(&env);
-    assert_eq!(
-        terminal,
-        terminal_info(
-            TerminalName::AppleTerminal,
-            /*term_program*/ None,
-            /*version*/ None,
-            /*term*/ None,
-            /*multiplexer*/ None
-        ),
-        "apple_term_session_id_info"
-    );
-    assert_eq!(
-        terminal.user_agent_token(),
-        "Apple_Terminal",
-        "apple_term_session_id_user_agent"
-    );
 }
 
 #[test]
@@ -735,7 +719,9 @@ fn detects_vte() {
 
 #[test]
 fn detects_windows_terminal() {
-    let env = FakeEnvironment::new().with_var("WT_SESSION", "1");
+    let env = FakeEnvironment::new()
+        .with_var("WT_SESSION", "1")
+        .with_var("TERM_SESSION_ID", "A1B2C3");
     let terminal = detect_terminal_info_from_env(&env);
     assert_eq!(
         terminal,
@@ -778,7 +764,9 @@ fn detects_windows_terminal() {
 
 #[test]
 fn detects_term_fallbacks() {
-    let env = FakeEnvironment::new().with_var("TERM", "xterm-256color");
+    let env = FakeEnvironment::new()
+        .with_var("TERM", "xterm-256color")
+        .with_var("TERM_SESSION_ID", "A1B2C3");
     let terminal = detect_terminal_info_from_env(&env);
     assert_eq!(
         terminal,