Adds encrypted cross-login sync for the NWC wallet connection (todo #15),
reusing the encrypted-sync core under d-tag "bitvid:nwc".
- js/services/settingsSyncFlags.js: shared per-pubkey opt-in flag store
(storage/wallet); storageSyncService refactored onto it (identical behavior,
tests still green).
- js/services/walletSyncService.js: factory (NwcSettingsService is per-app, not a
singleton). push() syncs the current nwcUri (+defaultZap); pull() applies it via
updateActiveNwcSettings; disable() wipes the note.
- Wallet pane (components/profile-modal.html + ProfileWalletController): opt-in
toggle + Restore button + a strong SPENDING warning, shown only when a signer
can encrypt. Enabling requires an explicit window.confirm (the URI can spend).
Re-pushes on save when enabled; and on wallet DISCONNECT while synced it clears
the note so a removed spending URI doesn't linger (encrypted) on relays.
tests/wallet-sync-service.test.mjs: enable-pushes-uri, pull-restores-via-
updateActiveNwcSettings, disable-clears, no-wallet-doesn't-publish. Mutation-
verified (skip-apply + skip-clear both fail).
Co-Authored-By: Claude Opus 4.8 <[email protected]>
