refactor: comprehensive codebase cleanup and architecture hardening

- Sprint 1 (Quick Wins): Remove dead analytics modules, fix 4 unresolved
  imports, replace 3 console.warn with logger, remove mock-crc import
- Sprint 2 (Architecture): Create MascotChatRepository, AnalysisRepository,
  3 Zod schemas (mascot-chat, analysis, voice), deduplicate error classes,
  move 3 SQL queries from routes to repository
- Sprint 3 (Complexity): Replace 7 any types with proper interfaces,
  extract 6 helpers from prepareMediaMessage (CC 85 -> ~15)
- Sprint 4 (Config): Remove 22 dead env vars from .env, add 30 missing
  vars to .env.example, standardize naming

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

services/discord-gateway/src/modules/command-handler/commandHandler.ts

@@ -377,7 +377,9 @@ export class CommandHandler {
     };
   }
 
-  private async handleVoiceTransmitStart(cmd: BackendCommand): Promise<CommandReply> {
+  private async handleVoiceTransmitStart(
+    cmd: BackendCommand,
+  ): Promise<CommandReply> {
     if (!discordPlayer.isConnected()) {
       return {
         id: cmd.id,
@@ -412,7 +414,9 @@ export class CommandHandler {
     }
   }
 
-  private async handleVoiceTransmitStop(cmd: BackendCommand): Promise<CommandReply> {
+  private async handleVoiceTransmitStop(
+    cmd: BackendCommand,
+  ): Promise<CommandReply> {
     try {
       await voiceTransmitter.stop();
       logger.info("Voice transmit stopped");
@@ -464,11 +468,9 @@ export class CommandHandler {
    * Fire-and-forget SET using the persistent Redis publisher connection.
    */
   private setKey(key: string, value: string): void {
-    this.redisPub
-      .set(key, value)
-      .catch((err: unknown) => {
-        const msg = err instanceof Error ? err.message : String(err);
-        logger.warn({ key, error: msg }, "Failed to update Redis status key");
-      });
+    this.redisPub.set(key, value).catch((err: unknown) => {
+      const msg = err instanceof Error ? err.message : String(err);
+      logger.warn({ key, error: msg }, "Failed to update Redis status key");
+    });
   }
 }