fix: correct transcendence guide copy and lifetime gold achievement tracking

Update How to Play guide to show prestige 20 threshold for transcendence
(was incorrectly showing 90). Switch gold achievement checks to use
lifetimeGoldEarned so progress persists across prestiges, matching the
"in total" wording of the achievement descriptions.

Closes #208
Closes #220

apps/web/src/components/game/aboutPanel.tsx

@@ -232,7 +232,7 @@ const howToPlay = [
   {
     body:
       "Transcendence is the ultimate prestige layer, unlocked by defeating"
-      + " The Absolute One (requires Prestige 90). Transcending performs a"
+      + " The Absolute One (requires Prestige 20). Transcending performs a"
       + " nuclear reset — wiping resources, prestige, runestones, upgrades,"
       + " and equipment — but grants Echoes based on your prestige count"
       + " (fewer prestiges = more Echoes). Echoes are permanent and survive"

apps/web/src/engine/tick.ts

@@ -41,7 +41,7 @@ const checkAchievements = (state: GameState): Array<Achievement> => {
 
     switch (condition.type) {
       case "totalGoldEarned":
-        met = state.player.totalGoldEarned >= condition.amount;
+        met = state.player.lifetimeGoldEarned >= condition.amount;
         break;
       case "totalClicks":
         met = state.player.totalClicks >= condition.amount;