feat(market): add asynchronous web market order queue processor (IOMarket::processWebOrders)

[berrytern]

Description

Integrating web-based marketplace purchases and sales with an active OpenTibia game server has historically been challenging due to the "dual-truth" memory problem:

• Modifying an online player's gold (balance) or inventory directly in MySQL leads to silent rollbacks when the C++ server saves the player's RAM state.
• Forcing players to always log out before buying/selling items on the website degrades the user experience.

This PR implements an Asynchronous Outbox Order Queue System directly in IOMarket::processWebOrders:

• A new table market_web_orders holds queued purchase requests submitted from web portals / AACs / APIs.
• The C++ engine polls pending orders on a configurable interval (default: 2000ms) on the Dispatcher thread.
• Hybrid RAM/DB Execution:
  • If buyer or seller is ONLINE: Modifies live player memory (player->getBankBalance(), player->setBankBalance(), internalAddItem()) and notifies the player in-game via text message.
  • If buyer or seller is OFFLINE: Safely executes atomic SQL balance debit/credit and delivers items directly into the player's depot inbox (player_depotitems).
• Automatically updates active market_offers and logs transaction history in market_history.

Behaviour

Actual

• Web market purchases required either fragile external database scripts or forced players to be offline, frequently causing memory overwrite bugs or 409 conflict rejections.

Expected

• External websites insert a row into market_web_orders with status 'PENDING'.
• The engine processes the order within ~1-2 seconds, atomically updating RAM (if players are online) or database (if players are offline), delivering items to Depot/Inbox, deducting/crediting gold or Tibia Coins, and marking the order 'COMPLETED'.
• Zero race conditions, zero rollbacks, and zero duplicated items.

Type of change

• New feature (non-breaking change which adds functionality)
• This change requires a documentation update

How Has This Been Tested

Test A: Web purchase with offline buyer and seller

1. Create a market offer:
   INSERT INTO market_offers (player_id, sale, itemtype, amount, created, anonymous, price, tier) VALUES (5, 1, 3360, 1, UNIX_TIMESTAMP(), 0, 15000, 0);
2. Insert a pending order in market_web_orders:
   INSERT INTO market_web_orders (offer_id, buyer_id, buyer_account_id, seller_id, seller_account_id, itemtype, amount, price, tier, currency_type, status, created_at) VALUES (LAST_INSERT_ID(), 4, 1, 5, 1, 3360, 1, 15000, 0, 'gold', 'PENDING', UNIX_TIMESTAMP());
3. Observe engine execution.
4. Result:
   • Order status transitions to 'COMPLETE

ℹ️ PR Dependency Note

This PR (feat/web-market-order-queue) is stacked on top of #908 (feat/player-concurrency-lock):

• feat(core): add database player concurrency lock to prevent web/game race conditions #908 implements the base database player concurrency lock mechanism (Migration 64.lua, db_version = 64).
• feat(market): add asynchronous web market order queue processor (IOMarket::processWebOrders) #909 implements the asynchronous web market order queue processor (Migration 65.lua, db_version = 65), building on top of the concurrency lock to ensure safe item deliveries and balance updates.

Merge Order:
Please review and merge #908 first.

[jprzimba]

Check Linux build error and fix please