Add multi-tenant cloud mode: self-serve purchase, credit metering, core-decoupling

Introduces RECAP_MODE=multi alongside single-mode self-host:
- Tenant auth + accounts (magic-link via System SMTP), per-tenant credit pool,
  anonymous trial minting with per-IP/-64 caps
- Self-serve Pro/Max purchase: inline Lightning (BTCPay) + card (Zaprite),
  prepaid 30-day periods, expiry-reminder emails
- Core-decoupling: relay owns cloud tier/expiry keyed by Recaps user-id
- SQLite (better-sqlite3) schema for multi-mode; filesystem unchanged for single
- StartOS actions/versions through 0.2.155

startos/actions/setAdminPassword.ts

@@ -43,7 +43,7 @@ export const setAdminPassword = sdk.Action.withInput(
   async ({ effects }) => ({
     name: 'Set Admin Password',
     description:
-      'Set a username and password that gate the Recap web UI. Anyone visiting the site (LAN or clearnet) must log in before reaching the activation screen. Leave the password blank to disable the gate.',
+      'Set a username and password that gate the Recaps web UI. Anyone visiting the site (LAN or clearnet) must log in before reaching the activation screen. Leave the password blank to disable the gate.',
     warning: null,
     allowedStatuses: 'any',
     group: 'Setup',