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

commands/economy_profile_commands.py

@@ -29,10 +29,15 @@ def register_economy_profile_commands(
         pct = progress / needed if needed > 0 else 1.0
         filled = int(pct * 12)
         bar = "█" * filled + "░" * (12 - filled)
-        embed = discord.Embed(
-            title=S.PROFILE_UI["main_title"].format(name=target.display_name),
-            color=0xF4C430,
+        badge = economy.vanity_badge(data)
+        title = (
+            f"{badge[0]} {target.display_name}"
+            if badge
+            else S.PROFILE_UI["main_title"].format(name=target.display_name)
         )
+        embed = discord.Embed(title=title, color=0xF4C430)
+        if badge:
+            embed.set_author(name=badge[1])
         embed.add_field(name=S.PROFILE_UI["f_balance"], value=coin(data.get("balance", 0)), inline=True)
         embed.add_field(
             name=S.PROFILE_UI["f_level"],