fix: clippy warnings and CI Node.js deprecation

- Remove unused imports in session.rs, buffer.rs, engine.rs
- Allow dead_code on intentionally unused fields (decoder, received_at)
- Allow enum_variant_names on Message enum
- Add FORCE_JAVASCRIPT_ACTIONS_TO_NODE24 to CI env

src/tsaudio/src/buffer.rs

@@ -1,7 +1,7 @@
 use std::collections::BTreeMap;
 use std::time::{Duration, Instant};
 
-use super::{AudioError, AudioFrame, AudioResult};
+use super::{AudioFrame, AudioResult};
 
 pub struct JitterBuffer {
     frames: BTreeMap<u16, BufferedFrame>,
@@ -15,6 +15,7 @@ pub struct JitterBuffer {
 
 struct BufferedFrame {
     frame: AudioFrame,
+    #[allow(dead_code)]
     received_at: Instant,
 }
 

src/tsaudio/src/engine.rs

@@ -1,9 +1,10 @@
 use crate::buffer::JitterBuffer;
 use crate::codec::OpusDecoder;
 use crate::playback::AudioPlayback;
-use crate::{AudioConfig, AudioError, AudioFrame, AudioResult};
+use crate::{AudioConfig, AudioFrame, AudioResult};
 
 pub struct VoiceEngine {
+    #[allow(dead_code)]
     decoder: OpusDecoder,
     jitter_buffer: JitterBuffer,
     playback: AudioPlayback,