Roadmap:
In this PR

• Remove deps on pubky-common and chrono
• Remove async
• Add pub functions to models new() default() create_path() to all models
• Improve tests
• Add missing models PubkyAppFeed and PubkyAppLastRead
• Add example usage
• Improve docs

Then:

• Integrate to Nexus Feat: integrate specs v0.2.1 pubky-nexus#233

In future PRs

• Build wasm-pack npmjs package
• Optimize wasm size
• Integrate to pubky-app

Then:

• Add workflows to trigger cargo publish and wasm-pack npm-publish on new tag release

Then:

• Figure migration to /v1 paths