Attachments, Protected Shares, Efficient Sync, and more

A huge branch of interrelated and breaking changes for Earthstar v10 Squirrel.

Adds attachments, so Earthstar can store large arbitrary binary data (thank you @achou11 for Node FS attachment drivers!)
Add share keypairs, so shares can have granular read write access
Add efficient sync (thank you for your help @AljoschaMeyer!)
New event APIs
Added a faster Sodium crypto driver
Added a fast Sqlite FFI driver
Improved querying performance (thank you for your help @basham!)
Added a common API for modifying a client's settings
Syncing a share's contents with the filesystem now supports large files
Multiformat support in replicas
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[x] Resolve merge conflicts
[x] Get CI passing again.
[x] Last scan for jsdocs
[x] Update CHANGELOG
[x] Do a big rewrite of README. Conceptual explanations of how syncing works; storage; attachments.

earthstar-project / earthstar