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/frontend/src/shared/ui/MobileTabBar.tsx

@@ -1,11 +1,10 @@
-import { BarChart3, MessageSquare, Radio } from "lucide-react";
+import { MessageSquare, Radio } from "lucide-react";
 import type { DashboardTab } from "../../entities/ui/types";
 import { cn } from "../lib/utils";
 
 const tabs: Array<{ id: DashboardTab; label: string; Icon: typeof Radio }> = [
   { id: "live", label: "Live", Icon: Radio },
   { id: "messages", label: "Messages", Icon: MessageSquare },
-  { id: "analytics", label: "Analytics", Icon: BarChart3 },
 ];
 
 interface MobileTabBarProps {

services/frontend/src/shared/ui/index.ts

@@ -1,6 +1,9 @@
 // ─── Shared UI barrel export ────────────────────────────────────────────────
 
-export { EmptyStateMascot, MascotImage } from "../../widgets/mascot/MascotImage";
+export {
+  EmptyStateMascot,
+  MascotImage,
+} from "../../widgets/mascot/MascotImage";
 export { Badge } from "./badge";
 export { Button } from "./button";
 export {