fix: pull-based audio playback eliminates drift + rustls crypto provider

Web playback rewritten from push-scheduling to pull-based ring buffer:
- ScriptProcessorNode pulls frames from buffer every ~21ms
- Buffer capped at 10 frames (~200ms) — drops oldest on overflow
- Latency permanently bounded, no drift over time

Also: install ring crypto provider for rustls TLS on Linux,
       build on debian-12 to match mequ glibc.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

crates/wzp-web/src/main.rs

@@ -32,6 +32,9 @@ struct AppState {
 #[tokio::main]
 async fn main() -> anyhow::Result<()> {
     tracing_subscriber::fmt().init();
+    rustls::crypto::ring::default_provider()
+        .install_default()
+        .expect("failed to install rustls crypto provider");
 
     let mut port: u16 = 8080;
     let mut relay_addr: SocketAddr = "127.0.0.1:4433".parse()?;