Send from hardware wallet

[ovitrif]

Part of #998.

Related (iOS): synonymdev/bitkit-ios#706

Design: Figma — HW Send

Scope

Paired Trezor wallets are funding sources in the normal on-chain Send flow.

• Scanner, paste, manual entry, and contacts can fund a send from a paired Trezor.
• Amount, fee selection, confirmation, device signing, broadcast, and success all run with the selected hardware identity.
• Lightning and LNURL requests explain that a Bitcoin address is required.
• Switching among Savings, Spending, and Trezor updates available balance and the fee-aware maximum.
• Passphrase identities reconnect to the matching hidden wallet before signing.
• Cancel or disconnect during signing recovers the session without broadcasting a duplicate.
• Pending sent activity and contact metadata stay attached while watcher snapshots catch up.

Send UI polish:

• Switching the funding source to Trezor keeps the source chip filled and shows a small spinner until the hardware fee is ready.
• Confirm keeps the previous fee with a spinner while the estimate refreshes.
• Swipe-to-confirm stays visible and stays blocked until the hardware fee is present.

[ovitrif]

Completed by #1195.

Implementation landed in #1187.