Franklin Agent 3.28.1 — onramp hardening from end-to-end review

• Popup blocker no longer eats the funding link — on block, the panel shows a clickable link (tokens stay valid ~5 min).
• Wallet card refreshes after minting — funding an empty wallet creates it; the UI now shows the address Coinbase is about to fund.
• Clear Base-only error on Solana instead of a crash inside payment signing.
• Gateway: free link minting now rate-limited (10/h per wallet, 30/h per IP).