fix(notes): add notes to saves filters

[marcin-kozinski]

Add a "Notes" chip to the Saves filter carousel:

• shows a placeholder text instead of notes for now,
• hidden behind a dev feature flag.

References

• https://mozilla-hub.atlassian.net/browse/POCKET-10877

PR Checklist

Setup:

• Described changes for automated release notes in PR title using
  Conventional Commits standard
• Self Review (review, clean up, documentation)
• Basic Self QA
• Feature flagged as needed to ensure this specific code is beta and production ready

Review:

• Code Review approved

[nzeltzer]

lgtm

[kschelonka]

there's a linter error but lgtm otherwise

[marcin-kozinski]

Thanks! Yea, the linter is a bit too eager, the problem it found will go away once Smartling updates the translated files. So in #137 I've updated the linter configuration to ignore translated files.