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/versions/v0.2.98.ts

@@ -0,0 +1,13 @@
+import { VersionInfo } from '@start9labs/start-sdk'
+
+export const v_0_2_98 = VersionInfo.of({
+  version: '0.2.98:0',
+  releaseNotes: {
+    en_US:
+      "Self-healing credit-purchase apply on multi-tenant cloud. When a buyer pays for credits via BTCPay, the relay's webhook credits the operator pool — but the buyer-side polling tab dies on the BTCPay → Recap redirect, so the local pending_purchases row never gets marked applied and the visible balance stays stale. Now every /api/account/whoami and /api/relay/status hit triggers a bounded sweep (max 5 invoices, 30-min lookback) that asks the relay for each unapplied invoice's status and runs apply for any that report settled. Idempotent via the existing applied_at column. Same sweep runs inside linkToUser BEFORE the anon-trial→user credit transfer, so a buy-then-immediately-sign-up flow rolls the just-purchased credits into the new user's balance instead of dropping them on the floor.",
+  },
+  migrations: {
+    up: async ({ effects }) => {},
+    down: async ({ effects }) => {},
+  },
+})