feat: handle unprotected session expiration (#747)

* feat: hide note contents if the protection expires when the protected note is open and wasn't edited for a while

* feat: handle session expiration for opened protected note for both plain advanced editors

* fix: if after canceling  session expiry modal only one unprotected note stays selected, show its contents in the editor

* refactor: handle session expiration for opened protected note (move the logic to web client)

* feat: handle the case of selecting "Don't remember" option in session expiry dialog

* test (WIP): add unit tests for protecting opened note after the session has expired

* test: add remaining unit tests

* refactor: move the opened note protection logic to "editor_view"

* refactor: reviewer comments
- don't rely on user signed-in/out status to require authentication for protected note
- remove unnecessary async/awaits
- better wording on ui

* refactor: reviewer's comments:
 - use snjs method to check if "Don't remember" option is selected in authentication modal
 - move the constant to snjs
 - fix eslint error

* refactor: avoid `any` type for `appEvent` payload

* test: add unit tests

* chore: update function name

* refactor: use simpler protection session event types

* refactor: protected access terminology

* refactor: start counting idle timer after every edit (instead of counting by interval in spite of edits)

* test: unit tests

* style: don't give extra brightness to the "View Note"/"Authenticate" button on hover/focus

* chore: bump snjs version

Co-authored-by: Mo Bitar <me@bitar.io>

app/assets/javascripts/views/editor/editor-view.pug

@@ -2,6 +2,7 @@
   protected-note-panel.h-full.flex.justify-center.items-center(
     ng-if='self.state.showProtectedWarning'
     app-state='self.appState'
+    require-authentication-for-protected-note='self.requireAuthenticationForProtectedNote'
     on-view-note='self.dismissProtectedWarning()'
   )
   .flex-grow.flex.flex-col(