503 shinytest2 for snapshot manager

[averissimo]

Pull Request

Part of https://github.com/insightsengineering/coredev-tasks/issues/503

🎯 ℹ️ Targets @main and (898_save_app_state3 silently)

• synced with latest e2e developments and bookmarking feature

👀 changed files of this PR are under:

• R/TealAppDriver.R
• tests/testthat/test-shinytest2-snapshot.R

Blocked by

• 🔴 Until #1011 is merged

Changes description

• Reintroduces snapshot manager testing
• Adds private field with prefix to teal application (instead of repeating teal-main_ui)
• Adds wunder_bar_ns function
  • Has id argument that optionally builds longer namespace (to use for snapshot_manager, filter_manager or bookmark_manager)