chore: community feedback fixes and UI improvements (#102)

## Summary

Addresses all community feedback tickets from the last deploy, plus several UI improvements made during the same session.

### Bug fixes & balance
- **#97** — Fix auto-adventurer tier priority: sort by combat power instead of current cost so the highest-tier affordable unit is always purchased
- **#98** — Add Dark Templar adventurer (80k CP) to bridge the Volcanic Depths progression wall; rewire upgrade and quest rewards accordingly
- **#99** — Reorder and buff Shadow Assassin (55k CP, level 12) so Witch Coven feels rewarding rather than a regression
- **#100** — Display effective Gold/s (all multipliers applied) in the resource bar
- **#101** — Add Peasant tier 2 (10x, essence) and tier 3 (50x, crystals) upgrades for meaningful late-game scaling

### Other fixes
- Sync game state to server before auto-boss challenges (matching manual challenge behaviour)
- Refresh Discord avatar hash on every game load via bot token so stale CDN URLs are corrected automatically

### UI improvements
- Replace Donate / Discord / Support / View Profile / Edit Profile buttons with a single avatar dropdown menu
- Collapse all resources except Gold into a click-to-toggle dropdown; orange alert dot appears when a hidden resource is capped

## Closes

Closes #97
Closes #98
Closes #99
Closes #100
Closes #101

Reviewed-on: #102
Co-authored-by: Hikari <hikari@nhcarrigan.com>
Co-committed-by: Hikari <hikari@nhcarrigan.com>

apps/api/src/data/quests.ts

@@ -183,6 +183,7 @@ export const defaultQuests: Array<Quest> = [
       { amount: 1500, type: "essence" },
       { amount: 75, type: "crystals" },
       { targetId: "knight_1", type: "upgrade" },
+      { targetId: "peasant_2", type: "upgrade" },
     ],
     status: "locked",
     zoneId: "shadow_marshes",
@@ -199,6 +200,7 @@ export const defaultQuests: Array<Quest> = [
       { amount: 8_000_000, type: "gold" },
       { amount: 2000, type: "essence" },
       { amount: 150, type: "crystals" },
+      { targetId: "dark_templar", type: "adventurer" },
     ],
     status: "locked",
     zoneId: "shadow_marshes",
@@ -281,6 +283,7 @@ export const defaultQuests: Array<Quest> = [
       { amount: 40_000_000, type: "gold" },
       { amount: 12_000, type: "essence" },
       { amount: 300, type: "crystals" },
+      { targetId: "peasant_3", type: "upgrade" },
     ],
     status: "locked",
     zoneId: "volcanic_depths",