feat: Implement clone_box for StripAnsiFilter and GrepFilter

Co-authored-by: aider (openai/andrew/openrouter/deepseek/deepseek-chat-v3.1) <aider@aider.chat>

src/filter_plugin/grep.rs

@@ -27,4 +27,10 @@ impl FilterPlugin for GrepFilter {
         }
         Ok(())
     }
+
+    fn clone_box(&self) -> Box<dyn FilterPlugin> {
+        Box::new(Self {
+            regex: self.regex.clone(),
+        })
+    }
 }

src/filter_plugin/mod.rs

@@ -11,6 +11,7 @@ pub mod utils;
 
 pub trait FilterPlugin: Send {
     fn filter(&mut self, reader: Box<&mut dyn Read>, writer: Box<&mut dyn Write>) -> Result<()>;
+    fn clone_box(&self) -> Box<dyn FilterPlugin>;
 }
 
 #[derive(Debug, EnumString, strum::VariantNames)]

src/filter_plugin/strip_ansi.rs

@@ -16,4 +16,8 @@ impl FilterPlugin for StripAnsiFilter {
         std::io::copy(&mut *reader, &mut ansi_writer)?;
         ansi_writer.flush()
     }
+
+    fn clone_box(&self) -> Box<dyn FilterPlugin> {
+        Box::new(Self)
+    }
 }