fix(favorites): open conversations with stored id

[RonenMars]

Summary

• carry each favorite persisted conversation ID into the Quick Access strip
• open pinned conversations with that ID instead of parsing the composite favorite key
• add an interaction regression test for the Favorites navigation path

Verification

• ESLint on the three changed files
• npm run typecheck
• focused Jest coverage: 3 suites, 20 tests passed
• full test run: 154 suites passed, 1350 tests passed, 1 skipped