feat: major endgame content expansion

- Add 6 new zones (Celestial Reaches through Eternal Throne) with sequential unlock chain
- Add 30 new bosses (5 per zone) scaling to 3e24 HP for true endgame challenge
- Add 36 new quests (6 per zone) with timers up to 96h for long-term progression
- Add 6 new adventurer tiers (seraph_knight through eternal_champion) requiring prestige 6-25
- Add ~36 new equipment pieces with boss drops and purchasable essence/crystal sinks
- Add new upgrades including endgame click/global multipliers and adventurer-specific unlocks
- Add 17 new achievements covering clicks (100K/1M), gold (quadrillion/quintillion), bosses (20/30/60), quests (30/50/72), adventurers (50K), prestige (5/10/25), and equipment (25/40)
- Extend formatNumber to support Q/Qt/S/Sp suffixes for numbers up to 1e24

apps/api/src/data/adventurers.ts

@@ -166,4 +166,70 @@ export const DEFAULT_ADVENTURERS: Adventurer[] = [
     count: 0,
     unlocked: false,
   },
+  {
+    id: "seraph_knight",
+    name: "Seraph Knight",
+    class: "paladin",
+    level: 16,
+    goldPerSecond: 1_200_000,
+    essencePerSecond: 800,
+    combatPower: 4_000_000,
+    count: 0,
+    unlocked: false,
+  },
+  {
+    id: "abyss_diver",
+    name: "Abyss Diver",
+    class: "rogue",
+    level: 17,
+    goldPerSecond: 3_500_000,
+    essencePerSecond: 2_000,
+    combatPower: 12_000_000,
+    count: 0,
+    unlocked: false,
+  },
+  {
+    id: "infernal_warden",
+    name: "Infernal Warden",
+    class: "warrior",
+    level: 18,
+    goldPerSecond: 10_000_000,
+    essencePerSecond: 5_000,
+    combatPower: 35_000_000,
+    count: 0,
+    unlocked: false,
+  },
+  {
+    id: "crystal_sage",
+    name: "Crystal Sage",
+    class: "mage",
+    level: 19,
+    goldPerSecond: 30_000_000,
+    essencePerSecond: 12_000,
+    combatPower: 100_000_000,
+    count: 0,
+    unlocked: false,
+  },
+  {
+    id: "void_sentinel",
+    name: "Void Sentinel",
+    class: "rogue",
+    level: 20,
+    goldPerSecond: 90_000_000,
+    essencePerSecond: 30_000,
+    combatPower: 300_000_000,
+    count: 0,
+    unlocked: false,
+  },
+  {
+    id: "eternal_champion",
+    name: "Eternal Champion",
+    class: "warrior",
+    level: 21,
+    goldPerSecond: 270_000_000,
+    essencePerSecond: 80_000,
+    combatPower: 900_000_000,
+    count: 0,
+    unlocked: false,
+  },
 ];