update to the venerable nostr-crdt package

• private crdt collaboration
• use ndk instead of nostr-tools
• use observableV2 to leverage patterns from y-webrtc and y-websocket communities
• drop boomer typescript support
• replace webpack/jest syntax with rollup.js and lib0/test

git clone https://github.com/colealbon/y-ndk.git;
cd y-ndk;
pnpm install;
pnpm test;
pnpm build;

nostr-crdt: https://github.com/YousefED/nostr-crdt
yjs: https://github.com/yjs/yjs
ndk: https://github.com/nostr-dev-kit/ndk
ndk-cli: https://github.com/nostr-dev-kit/ndk-cli
y-webrtc: https://github.com/yjs/y-webrtc
ssb-box: https://github.com/ssbc/ssb-box
private-box: https://github.com/auditdrivencrypto/private-box

we anticipate a client will pass in modern encrypt/decrypt functions - like whatever solidifies from this discussion:
MLS protocol: nostr-protocol/nips#1206 (comment)