Add 'deposit' as an alias for 'pay' in /firm command

Code context — "Pay into a firm" already exists: MiscCommands.payInto (@Route("pay into <firm> <amount>"), perm business.pay, open to anyone), plus a separate member-gated deposit <firm> <amount> (perm business.finance). Hibernia's @Route is @Repeatable, so adding an alias is just stacking a second @Route on the chosen handler.

Decision first: there's a naming collision — deposit is already a (gated) command. Should the new deposit alias the open pay into, or is this about the existing gated deposit? Resolve that, then it's a one-line annotation.