Submit Button & Mock Confirmation Modal

[0x-r4bbit]

The submit button and a confirmation modal that summarises the trade before the user "confirms". No real transaction is sent; the modal closes and resets the form.

Requirements

Button states:

State	Condition
Disabled — "Enter an amount"	No amount entered
Disabled — "Insufficient balance"	Amount exceeds user balance
Disabled — "Insufficient liquidity"	Output exceeds pool reserve
Active — "Swap"	All inputs valid

Confirmation modal:

• Summary of: you pay X Token A, you receive at least Y Token B
• Fee, price impact, slippage tolerance, min received
• "Confirm Swap" button → dismisses modal, shows a brief success toast, resets amounts
• "Cancel" button → dismisses modal, preserves amounts

Acceptance criteria

• Button label and disabled state reflect current input validity
• Modal renders the correct summary values (not stale)
• Confirming clears the input fields and shows a success toast
• Cancelling leaves all fields unchanged