Conditionally show Slippage field on the Swap UI

[elena-zh]

Reported and discussed in https://cowservices.slack.com/archives/C0361CDG8GP/p1759159316500599

Currently, the Slippage field is hidden in the price/costs accordion. However, sometimes it is needed to be displayed when a user changes the slippage manually/high slippage banner is displayed.

It would be great to move the slippage field outside the price/costs accordion when:

• a user manually changes it
• when we show a slippage warning (slippage is >2% for regular orders and >5% for eth-flow order on Mainnet)

Example:

[Rustix69]

@elena-zh Can I Pick up this Issue and work on ??

ETA : EOD

[elena-zh]

@elena-zh Can I Pick up this Issue and work on ??

ETA : EOD

Hi! Yes. Feel free to pick any task to work without prio-asking.
Thanks

[Grinsven]

This has never been picked up. Still an issue? @elena-zh

[elena-zh]

This has never been picked up. Still an issue? @elena-zh

Yes

[Grinsven]

Opened PR #6439 with the implementation. Shows slippage field outside accordion when modified, uses proper labels for different order types, and prevents duplication inside accordion for swap/bridge orders.