chore: add server switcher (#2717)

* wip

* wip2

* refactor: use radio button group

* chore: add persisting host per workspace

* chore: header style

* chore: update server picker title style

* chore: margin

* chore: label

* chore: remove separator

* rename migration to latest snjs version

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Co-authored-by: Aman Harwara <amanharwara@protonmail.com>

packages/snjs/lib/index.ts

@@ -7,6 +7,7 @@ export * from './Log'
 export * from './Migrations'
 export * from './Services'
 export * from './Types'
+export * from './Url'
 export * from './Version'
 export { KeyParamsOrigination } from '@standardnotes/common'
 export * from '@standardnotes/domain-core'