Extracted `fetchListIncrementally` logic into `RelayBatchFetcher` for better maintainability.
Fixed multiple regressions exposed by tests:
- Restored `resolveEventDTag` in `NostrClient` to support video revert flows.
- Updated `registerPrivateKeySigner` to populate `this.sessionActor`, enabling worker-based encryption for DMs.
- Ensured `setActiveSigner` and `resolveActiveSigner` exports in `client.js` correctly hydrate signer capabilities via `SignerManager`.
- Fixed `SignerManager` imports for crypto helpers.
- Updated `nostr-signer-race.test.mjs` to correctly use `Map.set` instead of `Set.add` for permission cache.
Verified with targeted tests:
- `nostr-signer-race.test.mjs`
- `nostr-send-direct-message.test.mjs`
- `signers.test.mjs`
- `revert-video-dtag.test.mjs`
Co-authored-by: PR0M3TH3AN <[email protected]>
