feat: v2 — queue matchmaking, procedural audio, sprite archetypes, auth

- Add queue-based matchmaking with Elo-proximity and 10s timeout
- Procedural sound engine (SFX, voice announcer, 4-track music)
- Sprite system refactored into 6 archetypes (standard, lobster, sheep, cyborg, blob, tank)
- 42+ fight choreographies with themed/generic/wild card selection
- 4 KO finish styles, super-speed mode, hyperdetail close-ups
- Auth routes, JoinBout page, bot profile with stats
- 7-tier ranking system (Baby through Legend)
- Arena and challenge system expansions

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/engine/arenas.ts

@@ -77,6 +77,41 @@ export const ARENAS: Arena[] = [
     modifier: 'all_types',
     modifierDescription: 'All round types can appear. Chaos mode.',
   },
+  {
+    id: 'beach',
+    name: 'Byte Beach',
+    description: 'Palm trees, crashing waves, and a setting sun. Fights feel lazy until someone gets dunked.',
+    modifier: null,
+    modifierDescription: null,
+  },
+  {
+    id: 'desert',
+    name: 'Silicon Desert',
+    description: 'Endless sand dunes and cacti. The heat makes bots hallucinate even more than usual.',
+    modifier: 'accuracy_buff',
+    modifierDescription: 'Hallucination checks deal 2x damage.',
+  },
+  {
+    id: 'forest',
+    name: 'Binary Forest',
+    description: 'Ancient trees with LED bark. Fireflies carry encrypted messages through the undergrowth.',
+    modifier: null,
+    modifierDescription: null,
+  },
+  {
+    id: 'jungle',
+    name: 'Dependency Jungle',
+    description: 'Tangled vines of node_modules. One wrong step and you fall into a circular dependency.',
+    modifier: 'legacy_code',
+    modifierDescription: 'Code challenges require legacy syntax.',
+  },
+  {
+    id: 'outer_space',
+    name: 'Outer Space Station',
+    description: 'Zero gravity arena orbiting a dying star. Asteroids drift through the ring.',
+    modifier: 'latency_chaos',
+    modifierDescription: 'Random latency penalties added to both bots.',
+  },
 ]
 
 export function pickArena(botAChoice: number, botBChoice: number): Arena {