docs: Update README.md

Add MetaMask wallet

Author: tokenpocketteam001

README.md

@@ -127,6 +127,7 @@ For full documentation, check out the README.md for each package or the [docs pa
 - [Frame](packages/frame/README.md)
 - [Blocto](packages/blocto/README.md)
 - [Particle Network](packages/particle-network/README.md)
+- [MetaMask](packages/metamask/README.md)
 
 **Hardware Wallets**