feat: wallet operations engine and encrypted storage with tests

src/lnurlcash/ops.ts

@@ -0,0 +1,35 @@
+// The operations engine: every multi-step wallet flow (carving exact
+// amounts, minting, receiving, paying), framework-free. Pinia stores call
+// these and apply the returned changesets; UI components never touch
+// lnurlcash-kit directly. Every function takes bearers in and returns the
+// new/changed notes out - it never mutates wallet state itself.
+//
+// Fund-critical invariants enforced across the flows (see the project plan):
+// - rotate on every receive, and immediately after claiming a fresh mint
+//   (observer race: anyone who saw the unpaid invoice knows the payment
+//   hash, and the mint necessarily saw the preimage - the preimage IS the
+//   note secret)
+// - a note's declared amount is a claim; the service's maxWithdrawable is
+//   authoritative
+// - a melt's "OK" only means the payment is in flight; its verify URL (or
+//   the note becoming spendable again) is the real outcome
+// - an ambiguous mutation NEVER loses the fresh secrets it carries: they
+//   are either rescued into tracked notes, probed, or surfaced to the
+//   caller unverified for later reconcile
+//
+// The engine is split by flow; this façade is the single import surface:
+//   ops/carve.ts         - ensureExactAmount (merge/split exact-amount carving)
+//   ops/mint.ts          - prepareMint / claimMintedNote (receive over Lightning)
+//   ops/receiveBearer.ts - receiveBearer (receive a note, rotate on receive)
+//   ops/pay.ts           - payWithBearers (melt to bolt11 / Lightning Address)
+//   ops/shared.ts        - bounded verify polling, UncertainOutcomeError
+
+export {UncertainOutcomeError} from './ops/shared'
+export type {PollOptions} from './ops/shared'
+export {ensureExactAmount} from './ops/carve'
+export type {CarveResult} from './ops/carve'
+export {prepareMint, claimMintedNote} from './ops/mint'
+export type {PreparedMint, ClaimedNote} from './ops/mint'
+export {receiveBearer} from './ops/receiveBearer'
+export {payWithBearers} from './ops/pay'
+export type {PayOutcome, PayResult, PayOptions} from './ops/pay'