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/heist.py

@@ -8,7 +8,7 @@ from .. import pb_client
 from ..pb_client import DatabaseError
 from . import house
 from .store import HEIST_JAIL, _commit, _is_jailed, _now, _txn, _user_lock, get_user
-from .house import _credit_house, _refund_house_safe, _refund_user_safe
+from .house import _credit_house, _refund_house_safe, _debit_house_safe
 
 
 # ---------------------------------------------------------------------------
@@ -98,6 +98,6 @@ async def do_heist_resolve(user_ids: list[int], success: bool) -> dict:
                 if success and payout_each > 0:
                     await _refund_house_safe(payout_each, "heist_win_compensate", uid)
                 elif not success and fine_credited:
-                    await _refund_user_safe(house.HOUSE_ID, fine if 'fine' in locals() else 0, "heist_fail_compensate", uid)
+                    await _debit_house_safe(fine if 'fine' in locals() else 0, "heist_fail_compensate", uid)
 
     return {"ok": True, "payout_each": payout_each, "success": success, "failed_users": failed_users}