[ 398ja/cashu-voucher ] docs: update documentation for Schnorr signatures and version 0.3.6
Updated all references from Ed25519 to secp256k1 Schnorr (BIP-340) signatures and revised key generation examples. Bumped dependency and documentation versions to 0.3.6 accordingly.
[ flox1an/nostube ] fix: video server availability HEAD request loop
Fixed continuous HEAD requests to Blossom servers when checking video
availability. The caching mechanism was broken because setting status
to 'checking' would overwrite the `lastChecked` timestamp, causing the
cache check to fail on subsequent calls.
Changes:
- Preserve `lastChecked` when transitioning to 'checking' status
- Use stable empty array constant for `videoUrls` to prevent unnecessary