The terminal's subscriptions screen adds a Claude account with `a` (token typed masked) and removes one with `D` after a confirm, as MCP `subscription_add` and `subscription_delete` do #7440

Intent: the owner manages the crew's pool of Claude accounts from the terminal, not only wakes and budgets them.

Today src/tui/screens/subscriptions.ts offers b (budget) and w (wake), but no add or remove.

Done:

• [ ] a asks for a name, then the token typed masked, then an optional API base. It calls addSubscription (src/core/subscriptions.ts) and uses the refusals from addRefusal word for word. The token is handed over once and never held, drawn or logged.
• [ ] D on the selected subscription shows what goes (the subscription and its grants; past runs keep it in their history) and, after a confirm, calls deleteSubscription.
• [ ] Only a forge admin who is a person is offered either key. An agent sees no key and changes nothing.
• [ ] A test (e.g. test/tui-subscriptions-add.test.ts) adds one and sees it listed, checks the token never appears in any drawn frame, removes it after a confirm, and checks that a cancelled confirm changes nothing.

Files: src/tui/screens/subscriptions.ts, a new test.