chore(services): update components based on recent changes

Changes:
 services/discord-gateway/src/modules/voice-pcm-ws/index.ts            |   1 +
 services/discord-gateway/src/modules/voice-pcm-ws/voicePcmWsClient.ts | 151 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 152 insertions(+)

services/discord-gateway/src/modules/voice-pcm-ws/index.ts

@@ -0,0 +1 @@
+export { VoicePcmWsClient } from "./voicePcmWsClient.js";

services/discord-gateway/src/modules/voice-pcm-ws/voicePcmWsClient.ts

@@ -0,0 +1,151 @@
+/**
+ * Direct WebSocket client for streaming voice PCM to the backend.
+ *
+ * Bypasses Redis pub/sub entirely — gateway connects as a WS client
+ * to the backend's existing WebSocket server and sends pre-formatted
+ * binary frames (4-byte FNV-1a userId hash + raw Int16LE PCM).
+ * The backend forwards these unchanged to frontend clients.
+ */
+
+import { createChildLogger } from "@bete/shared/logger";
+import WebSocket from "ws";
+
+const logger = createChildLogger("voice-pcm-ws");
+
+/** 32-bit FNV-1a hash — mirrors backend/ws/redis-bridge.ts and frontend useAudioPlayback.ts */
+function hashUserId(userId: string): number {
+  let hash = 0x811c9dc5;
+  for (let i = 0; i < userId.length; i++) {
+    hash ^= userId.charCodeAt(i);
+    hash = Math.imul(hash, 0x01000193);
+  }
+  return hash >>> 0;
+}
+
+export class VoicePcmWsClient {
+  private ws: WebSocket | null = null;
+  private readonly token: string;
+  private readonly url: string;
+  private reconnectTimer: ReturnType<typeof setTimeout> | null = null;
+  private closed = false;
+  private reconnectMs = 1000;
+
+  constructor(url: string, token: string) {
+    this.url = url;
+    this.token = token;
+  }
+
+  /** Open connection and begin automatic reconnect loop. */
+  connect(): void {
+    if (this.closed) return;
+    this.doConnect();
+  }
+
+  /**
+   * Send a PCM chunk to the backend.
+   *
+   * Binary frame format (identical to what frontend expects):
+   *   Byte 0–3:  FNV-1a 32-bit userId hash (UInt32LE)
+   *   Byte 4+:   PCM audio (24kHz mono Int16LE)
+   *
+   * Silently drops if not connected — real-time audio, stale
+   * chunks from a disconnect gap are useless.
+   */
+  sendPcm(userId: string, pcmBuffer: Buffer): void {
+    if (!this.ws || this.ws.readyState !== WebSocket.OPEN) return;
+
+    const hash = hashUserId(userId);
+    const frame = Buffer.alloc(4 + pcmBuffer.length);
+    frame.writeUInt32LE(hash, 0);
+    pcmBuffer.copy(frame, 4);
+
+    try {
+      this.ws.send(frame);
+    } catch (err) {
+      logger.warn({ err }, "Failed to send PCM frame");
+    }
+  }
+
+  /** Graceful close — send close frame, clear reconnect timer. */
+  async close(): Promise<void> {
+    this.closed = true;
+    this.clearReconnectTimer();
+
+    if (!this.ws) return;
+
+    // Remove listeners so reconnect doesn't fire during close
+    this.ws.removeAllListeners();
+
+    if (this.ws.readyState === WebSocket.OPEN) {
+      this.ws.close(1000, "shutdown");
+    }
+
+    this.ws = null;
+  }
+
+  // ── internals ────────────────────────────────────────────────────────
+
+  private getUrlWithAuth(): string {
+    const sep = this.url.includes("?") ? "&" : "?";
+    return `${this.url}${sep}token=${encodeURIComponent(this.token)}`;
+  }
+
+  private doConnect(): void {
+    if (this.closed) return;
+
+    const authUrl = this.getUrlWithAuth();
+    logger.info({ url: this.url }, "Connecting to backend WebSocket");
+
+    try {
+      this.ws = new WebSocket(authUrl);
+    } catch (err) {
+      logger.error({ err }, "Failed to create WebSocket");
+      this.scheduleReconnect();
+      return;
+    }
+
+    this.ws.on("open", () => {
+      logger.info("Voice PCM WS client connected");
+      this.reconnectMs = 1000; // reset backoff on successful connect
+    });
+
+    this.ws.on("close", (code, reason) => {
+      logger.warn(
+        { code, reason: reason.toString() },
+        "Voice PCM WS client disconnected",
+      );
+      this.ws = null;
+      this.scheduleReconnect();
+    });
+
+    this.ws.on("error", (err) => {
+      logger.error({ err: err.message }, "Voice PCM WS client error");
+      // on("close") fires after on("error") — reconnect handled there
+    });
+  }
+
+  private scheduleReconnect(): void {
+    if (this.closed) return;
+    this.clearReconnectTimer();
+
+    // Exponential backoff with jitter: 1s → 2s → 4s → ... → 30s cap
+    const delay = this.reconnectMs + Math.random() * 1000;
+    logger.info({ delayMs: Math.round(delay) }, "Scheduling WS reconnect");
+
+    this.reconnectTimer = setTimeout(() => {
+      this.reconnectTimer = null;
+      if (!this.closed) {
+        this.doConnect();
+      }
+    }, delay);
+
+    this.reconnectMs = Math.min(this.reconnectMs * 2, 30_000);
+  }
+
+  private clearReconnectTimer(): void {
+    if (this.reconnectTimer !== null) {
+      clearTimeout(this.reconnectTimer);
+      this.reconnectTimer = null;
+    }
+  }
+}