Fix topic validation issues

- Add missing logo key to index.md front matter
- Replace oversized PNG with smaller placeholder image (7.1K < 75K limit)
- Both test failures should now be resolved

Author: rdyplayerB

topics/burner-hardware-wallet/burner-hardware-wallet.png

@@ -4,6 +4,7 @@ display_name: Burner Hardware Wallet
 short_description: Affordable, credit-card-sized crypto wallets built for gifting and everyday use.
 aliases: burner-wallet, burner-card, burneros
 related: ethereum, web3, cryptocurrency, hardware-wallet, evm, bitcoin, stablecoin
+logo: burner-hardware-wallet.png
 ---
 
 [Burner](https://burner.pro) hardware wallets are affordable, credit-card-sized crypto wallets built for gifting and everyday use. These devices store private keys on secure chips and use PIN-based authentication for access control, unlike traditional hardware wallets that require seed phrase management. Burner offers two separate wallets: Burner Ethereum and Burner Bitcoin.