feat: use isatty::tty_path for TTY detection in meta plugin

Co-authored-by: aider (openai/andrew.openrouter.qwen.qwen3-coder) <aider@aider.chat>

src/meta_plugin/system.rs

@@ -378,30 +378,15 @@ impl MetaPlugin for TtyMetaPlugin {
     }
 
     fn finalize(&mut self) -> io::Result<String> {
-        // Try to get TTY from /proc/self/stat
-        match std::fs::read_to_string("/proc/self/stat") {
-            Ok(stat_content) => {
-                // The 7th field (index 6) in /proc/self/stat contains the controlling terminal (TTY)
-                let fields: Vec<&str> = stat_content.split_whitespace().collect();
-                if fields.len() > 6 {
-                    if let Ok(tty_nr) = fields[6].parse::<u32>() {
-                        if tty_nr != 0 {
-                            // Convert tty_nr to device path
-                            match self.tty_name(tty_nr) {
-                                Some(tty_name) => return Ok(tty_name),
-                                None => return Ok("unknown tty".to_string()),
-                            }
-                        }
-                    }
+        // Use isatty::tty_path to get the current TTY path
+        match isatty::stdout_isatty() {
+            true => {
+                match isatty::tty_path() {
+                    Ok(path) => Ok(path.to_string_lossy().to_string()),
+                    Err(_) => Ok("unknown tty".to_string()),
                 }
-            }
-            Err(_) => {}
-        }
-        
-        // Fallback: try to get TTY from /dev/tty
-        match std::fs::read_link("/dev/tty") {
-            Ok(path) => Ok(format!("/dev/{}", path.to_string_lossy())),
-            Err(_) => Ok("not a tty".to_string()),
+            },
+            false => Ok("not a tty".to_string()),
         }
     }
 
@@ -413,36 +398,3 @@ impl MetaPlugin for TtyMetaPlugin {
         self.meta_name.clone()
     }
 }
-
-impl TtyMetaPlugin {
-    // Convert tty device number to device name
-    fn tty_name(&self, tty_nr: u32) -> Option<String> {
-        let major = (tty_nr >> 8) as u16;
-        let minor = (tty_nr & 0xff) as u16;
-        
-        // Handle common TTY device types
-        match major {
-            4 => {
-                // TTY devices
-                if minor < 64 {
-                    Some(format!("/dev/tty{}", minor))
-                } else {
-                    None
-                }
-            },
-            136..=143 => {
-                // PTS devices
-                Some(format!("/dev/pts/{}", minor))
-            },
-            3 => {
-                // TTY devices
-                if minor < 64 {
-                    Some(format!("/dev/tty{}", minor))
-                } else {
-                    None
-                }
-            },
-            _ => None,
-        }
-    }
-}