Implement bank, guild bank, and auction house systems

Add 27 new opcodes, packet builders/parsers, handler methods, inventory
extension with 28 bank slots + 7 bank bags, and UI windows for personal
bank, guild bank (6 tabs x 98 slots), and auction house (browse/sell/bid).
Fix Classic gossip parser to omit boxMoney/boxText fields not present in
Vanilla protocol, fix gossip icon labels with text-based NPC type detection,
and add Turtle WoW opcode mappings for bank and auction interactions.

include/game/opcode_table.hpp

@@ -382,6 +382,39 @@ enum class LogicalOpcode : uint16_t {
     SMSG_RECEIVED_MAIL,
     MSG_QUERY_NEXT_MAIL_TIME,
 
+    // ---- Bank ----
+    CMSG_BANKER_ACTIVATE,
+    SMSG_SHOW_BANK,
+    CMSG_BUY_BANK_SLOT,
+    SMSG_BUY_BANK_SLOT_RESULT,
+    CMSG_AUTOBANK_ITEM,
+    CMSG_AUTOSTORE_BANK_ITEM,
+
+    // ---- Guild Bank ----
+    CMSG_GUILD_BANKER_ACTIVATE,
+    CMSG_GUILD_BANK_QUERY_TAB,
+    SMSG_GUILD_BANK_LIST,
+    CMSG_GUILD_BANK_SWAP_ITEMS,
+    CMSG_GUILD_BANK_BUY_TAB,
+    CMSG_GUILD_BANK_UPDATE_TAB,
+    CMSG_GUILD_BANK_DEPOSIT_MONEY,
+    CMSG_GUILD_BANK_WITHDRAW_MONEY,
+
+    // ---- Auction House ----
+    MSG_AUCTION_HELLO,
+    CMSG_AUCTION_SELL_ITEM,
+    CMSG_AUCTION_REMOVE_ITEM,
+    CMSG_AUCTION_LIST_ITEMS,
+    CMSG_AUCTION_LIST_OWNER_ITEMS,
+    CMSG_AUCTION_PLACE_BID,
+    SMSG_AUCTION_COMMAND_RESULT,
+    SMSG_AUCTION_LIST_RESULT,
+    SMSG_AUCTION_OWNER_LIST_RESULT,
+    SMSG_AUCTION_BIDDER_LIST_RESULT,
+    SMSG_AUCTION_OWNER_NOTIFICATION,
+    SMSG_AUCTION_BIDDER_NOTIFICATION,
+    CMSG_AUCTION_LIST_BIDDER_ITEMS,
+
     // Sentinel
     COUNT
 };