gas UX: flat 1 GNOT in gnoweb commands, no estimation, no link after deploy #6276

Status 2026-10-28. Nothing below has changed on master. Related work since: the copied commands themselves have two bugs (#6385, #6386; fixes in #6419, #6418), and #6313 makes a simulation report the real gas used, which estimation needs.

Problem

Gas is where a first transaction goes wrong, and on mainnet it costs real money.

• gnoweb charges a flat 1 GNOT. Every command the Actions panel offers for copy-paste hardcodes -gas-fee 1000000ugnot -gas-wanted 1_000_000_000 (components/ui/command.html:15-16). Unused gas is not refunded, so each copied call costs 1 GNOT whatever it actually uses. Lowering only the fee makes the tx fail with insufficient fee: gas-wanted has to come down with it, or be simulated.
• No automatic estimation. Builders guess -gas-wanted by hand. feat(gnokey): --gas-wanted=auto --gas-fee=auto #4451 was closed without merging, and only -gas-fee-margin (chore(gnokey): Add simulate optional parameter -gas-fee-margin #5112) landed.
• No link after deploy. addpkg prints PKGPATH: but not the URL where the realm can be seen.

To do

• gnoweb: a measured default, or simulate before suggesting the command.
• gnokey: opt-in gas estimation (-gas-wanted auto or similar). Also asked in META Improving gnokey UX #3703; feat(tm2): meter simulations at the block max gas #6313 is the node side.
• gnokey and gnodev: print the realm URL after a successful addpkg.

Comes from #6121 §1.4 and #5460. Related: #5087, #3703.