refactor: Use io::copy to simplify StripAnsiFilter

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

src/filter_plugin/strip_ansi.rs

@@ -1,7 +1,5 @@
 use std::io::{Result, Read, Write};
 use strip_ansi_escapes::Writer;
-use crate::common::PIPESIZE;
-
 use super::FilterPlugin;
 
 pub struct StripAnsiFilter;
@@ -14,16 +12,8 @@ impl StripAnsiFilter {
 
 impl FilterPlugin for StripAnsiFilter {
     fn filter<R: Read, W: Write>(&mut self, reader: &mut R, writer: &mut W) -> Result<()> {
-        let mut buffer = vec![0; PIPESIZE];
         let mut ansi_writer = Writer::new(writer);
-        
-        loop {
-            let bytes_read = reader.read(&mut buffer)?;
-            if bytes_read == 0 {
-                break;
-            }
-            ansi_writer.write_all(&buffer[..bytes_read])?;
-        }
+        std::io::copy(reader, &mut ansi_writer)?;
         ansi_writer.flush()?;
         Ok(())
     }