chore(services): update components based on recent changes

Changes:
 services/backend/src/ws/redis-bridge.ts                | 31 ++++++++++++++++++++-
 services/backend/src/ws/server.ts                      | 36 +++++++++++++++++++++++-
 services/frontend/src/App.tsx                          | 12 ++++----
 services/frontend/src/shared/hooks/useAudioPlayback.ts | 91 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 services/frontend/src/shared/hooks/useAudioTransmit.ts | 21 +++++---------
 5 files changed, 169 insertions(+), 22 deletions(-)

services/backend/src/ws/redis-bridge.ts

@@ -25,7 +25,7 @@ import {
 import { createChildLogger } from "@bete/shared/logger";
 import Redis from "ioredis";
 import { config } from "../shared/config/index.js";
-import { broadcastEvent } from "./broadcast.js";
+import { broadcastBinary, broadcastEvent } from "./broadcast.js";
 
 const logger = createChildLogger("ws.redis-bridge");
 
@@ -96,6 +96,25 @@ function handleSubscriptionMessage(channel: string, message: string): void {
   // We only want <actual payload>, not the full envelope.
   const data = envelope.data !== undefined ? envelope.data : envelope;
 
+  // Voice PCM: decode base64 → binary broadcast instead of JSON
+  if (mapping.eventType === "voice_pcm_data") {
+    const pcmPayload = data as { userId?: string; pcm?: string };
+    if (pcmPayload?.pcm && pcmPayload?.userId) {
+      try {
+        const pcmBuffer = Buffer.from(pcmPayload.pcm, "base64");
+        // Prepend userId as 4-byte FNV-1a hash
+        const userIdHash = hashUserId(pcmPayload.userId);
+        const binary = Buffer.alloc(4 + pcmBuffer.length);
+        binary.writeUInt32LE(userIdHash, 0);
+        pcmBuffer.copy(binary, 4);
+        broadcastBinary(binary);
+        return;
+      } catch {
+        // fallback to JSON broadcast on error
+      }
+    }
+  }
+
   logger.debug(
     { channel, eventType: mapping.eventType },
     "Broadcasting Redis event",
@@ -103,6 +122,16 @@ function handleSubscriptionMessage(channel: string, message: string): void {
   broadcastEvent(mapping.eventType, data);
 }
 
+/** Simple 32-bit FNV-1a hash for userId → 4-byte identifier */
+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 async function startRedisBridge(): Promise<void> {
   if (!config.REDIS_URL) {
     logger.info("Redis not configured, skipping Redis bridge");

services/backend/src/ws/server.ts

@@ -78,6 +78,40 @@ export function createWebSocketServer(server: Server): WebSocketServer {
     );
 
     ws.on("message", (data: Buffer) => {
+      // Handle binary PCM from browser (FE→Discord transmit)
+      // Format: 4-byte magic "PCM\0" + raw PCM Int16 LE
+      if (
+        Buffer.isBuffer(data) &&
+        data.length > 4 &&
+        data[0] === 0x50 && // 'P'
+        data[1] === 0x43 && // 'C'
+        data[2] === 0x4d && // 'M'
+        data[3] === 0x00    // '\0'
+      ) {
+        const pcmBuffer = data.subarray(4);
+        const base64 = pcmBuffer.toString("base64");
+        import("../shared/redis/index.js").then(
+          ({ getCommandPublisher }) => {
+            const publisher = getCommandPublisher();
+            publisher
+              .publish(
+                BACKEND_VOICE_TRANSMIT,
+                JSON.stringify({
+                  type: "pcm",
+                  buffer: base64,
+                }),
+              )
+              .catch((err: Error) => {
+                logger.error(
+                  { err },
+                  "Failed to publish voice transmit to Redis",
+                );
+              });
+          },
+        );
+        return;
+      }
+
       // Handle JSON messages from browser
       if (
         typeof data === "string" ||
@@ -87,7 +121,7 @@ export function createWebSocketServer(server: Server): WebSocketServer {
           const message = JSON.parse(data.toString());
 
           if (message.type === "voice_transmit" && message.buffer) {
-            // Forward PCM data to Redis for discord-gateway
+            // Legacy: Forward PCM data to Redis for discord-gateway
             import("../shared/redis/index.js").then(
               ({ getCommandPublisher }) => {
                 const publisher = getCommandPublisher();