make work with delegated contract wallet key

[frrist]

To improve security, we can delegate session keys from the main wallet for signing operations (see FilOzone SessionKeyRegistry). This approach reduces exposure of the main private key while maintaining operational flexibility by allowing the signing service to sign transactions without a dependency on the main USDFC wallet.

[travis]

there's an open question in a notion doc @frrist wrote about this - @frrist will add a bit more detail to this ticket

[frrist]

Open question if we do this in doc here: https://www.notion.so/storacha/Storacha-Forge-Contract-Billing-Operations-Design-Questions-28b5305b552480d08ea7c8a1ff077a2d?source=copy_link#2955305b552480c5a453f62d82ae772f