feat(economy): add vanity shop and harden economy money-safety

Vanity shop (/vanity): cosmetic badges/titles as a pure whale coin sink -
purchases burn coins (not credited to the house) and equip a badge shown on
/profile. New vanity_owned/vanity_active fields, schema sync, and tests.

Money-safety and robustness fixes from a codebase review:

- _parse_amount now rejects negative amounts. Every bet/give/request flows
  through it, so a negative value can no longer mint coins on a loss/transfer
  path that trusts the caller's sign (all call sites already guarded <= 0;
  this closes the source).
- do_blackjack_payout no longer raises on a DB failure. The stake was already
  deducted in do_blackjack_bet, so it now logs critical with the owed amount
  (for admin reconciliation) and returns db_error; all payout call sites render
  a clear "payout failed" notice instead of crashing the interaction.
- Instant "kohv" consumable now cancels the pending reminder DMs for the
  cooldowns it wipes (via new INSTANT_RESET_COMMANDS), so no stale/duplicate
  reminders fire.
- Renamed the misleadingly-named _refund_user_safe -> _debit_house_safe (it
  debits the house) and dropped its ignored first arg.
- Added __all__ to vanity.py and consumables.py so `import *` no longer leaks
  incidental imports into the economy namespace.
- Documented Kõrvaklapid's +25 coin daily bonus in README and DEV_NOTES.

Tests: blackjack payout DB-failure safety and INSTANT_RESET_COMMANDS lockstep.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013VbAVsrZuYesea99mPMmPT

core/economy/gambling.py

@@ -6,7 +6,7 @@ import random
 
 from ..pb_client import DatabaseError
 from ..emoji import EMOJI as E
-from .store import _commit, _is_jailed, _locked_by, _txn, get_user
+from .store import _commit, _is_jailed, _locked_by, _log, _txn, get_user
 from .house import _credit_house
 
 
@@ -254,8 +254,15 @@ async def do_blackjack_bet(user_id: int, bet: int) -> dict:
 
 @_locked_by(0)
 async def do_blackjack_payout(user_id: int, payout: int, total_invested: int = 0) -> dict:
-    """Credit the net payout. House receives the difference when payout < total_invested."""
-    user = await get_user(user_id)
+    """Credit the net payout. House receives the difference when payout < total_invested.
+
+    The stake was already deducted in do_blackjack_bet, so a DB failure here must
+    not raise through the interaction handler and swallow the player's winnings:
+    report db_error like every other mutation so the caller can surface it."""
+    try:
+        user = await get_user(user_id)
+    except DatabaseError:
+        return {"ok": False, "reason": "db_error"}
     user["balance"] += payout
     user["balance"] = max(0, user["balance"])
     user["total_wagered"] = user.get("total_wagered", 0) + total_invested
@@ -267,7 +274,17 @@ async def do_blackjack_payout(user_id: int, payout: int, total_invested: int = 0
     elif net < 0:
         user["lifetime_lost"] = user.get("lifetime_lost", 0) + abs(net)
         user["biggest_loss"] = max(user.get("biggest_loss", 0), abs(net))
-    await _commit(user_id, user)
+    try:
+        await _commit(user_id, user)
+    except DatabaseError:
+        # The stake is already gone (deducted in do_blackjack_bet) and this credit
+        # did not persist. Nothing to roll back locally - log the owed amount so an
+        # admin can reconcile with /admincoins.
+        _log.critical(
+            "blackjack payout commit failed for %s: owed payout=%s (invested=%s)",
+            user_id, payout, total_invested,
+        )
+        return {"ok": False, "reason": "db_error"}
     house_gain = total_invested - payout
     if house_gain > 0:
         await _credit_house(house_gain)