Summary

• When the b20 demo pays gas in a stablecoin, the fee is paid by transferring the token to the AA payer as phase 0 of the account-abstraction batch rather than through any dedicated receipt field — so the explorer's tx detail page only ever showed the ETH-denominated gas fee, never the token amount actually paid.
• Added findGasTokenFee in app/vibenet/library/explorer.ts, which detects that phase-0 pattern (a lone transfer(payer, amount) call) and returns the token contract + raw amount.
• Added app/vibenet/library/token.ts to resolve the token's symbol()/decimals() on chain (the receipt has no metadata for an arbitrary user-deployed b20 token), so the row reads e.g. 0.1 RWRD instead of raw units.
• Wired into the tx detail page as a "Gas token fee" row: falls back to raw units + a link to the token contract while the symbol lookup is in flight or fails.
• When gas was paid in a token, the ETH fee row is relabeled "Network cost" and dimmed with "(paid by payer)" instead of "Fee" — it's not what the user paid, but it's still useful for debugging whether the payer's flat token fee actually covers what it spends in ETH. Gas limit/used/effective gas price are left as-is (they describe network execution, not what the user paid).

Test plan

• npx tsc --noEmit — clean
• npx vitest run app/vibenet/library/explorer.test.ts — 29/29 passing (3 new cases for findGasTokenFee: happy path, no-payer/no-aa, false-positive guards)
• npx eslint on changed files — no new warnings/errors beyond pre-existing ones in this file

Before

After