feat: add tty meta plugin to get current terminal device

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

src/meta_plugin.rs

@@ -33,6 +33,7 @@ pub enum MetaPluginType {
     ReadRate,
     Hostname,
     FullHostname,
+    Tty,
 }
 
 pub trait MetaPlugin {
@@ -75,6 +76,7 @@ pub fn get_meta_plugin(meta_plugin_type: MetaPluginType) -> Box<dyn MetaPlugin>
         MetaPluginType::ReadRate => Box::new(ReadRateMetaPlugin::new()),
         MetaPluginType::Hostname => Box::new(HostnameMetaPlugin::new()),
         MetaPluginType::FullHostname => Box::new(FullHostnameMetaPlugin::new()),
+        MetaPluginType::Tty => Box::new(TtyMetaPlugin::new()),
     }
 }