nwc: enforce per-connection spend budgets + flag-gated incident containment

Thread the remaining allowance through every spend path (pay_invoice, pay,
pay_keysend, internal transfer) as maxTotal, and have debit() assert the spend
stays within it after it reloads the invoice and captures the tip — so a
delegated NWC credential can no longer exceed its configured budget, and a
mutated tip can't slip a small-budget check and drain via the internal path.
checkBudget now returns the remaining allowance alongside any error; a blank
budget is treated as deliberately unlimited and a positive budget requires a
known renewal period.

Add operator-controlled containment for a suspected credential disclosure, all
gated behind Redis flags with no hardcoded scope:
  nwc:disabled              fail every method closed
  nwc:credential-cutoff     retire connections created before an epoch
  nwc:quarantined           block an individual disclosed connection
  nwc:guard:dormant-keysend  quarantine the first keysend on a long-idle app

Fix an ownership check that read the bare pubkey instead of app:<pubkey>, which
let an authenticated user overwrite another connection's config, and validate
budget/fee/renewal inputs.

Co-Authored-By: Claude Opus 4.8 <[email protected]>
Claude-Session: https://claude.ai/code/session_01XiwgmQKwKnRxUmVDd4xSf7

0 files changed, 0 insertions, 0 deletions