docs: update quickstart and references for embedded replica updates

[notrab]

Rust

• [x] Document periodic sync
• [x] Document encryption at rest

Go

• [x] Update Quickstart with AutoSync duration example
• [x] Add Reference page
• • [x] Document manual/periodic sync
• • [x] Document encryption at rest

TS

• [x] Document periodic sync
• [x] Document encryption at rest

[notrab]

@LucioFranco @penberg if you both are happy (once rust crate is published) we can merge this.