Posthog webview experiments

[mwvolo]

This pull request introduces comprehensive integration with PostHog analytics throughout the application, enabling detailed event tracking, user identification, and feature flag-driven UI experimentation. The changes include a new helper module for PostHog, event capture on key user actions, user identification management, and feature flag usage for conditional UI rendering, especially in navigation menus.

Analytics Integration and Event Tracking:

• Added a new posthog.ts helper module with utility functions for capturing events, identifying users, registering properties, and reading feature flags; includes a custom React hook for flag-driven UI updates.
• Instrumented key user actions with captureEvent calls:
  • Book selection/deselection in BookSelector (book_selected) [1] [2] [3] [4]
  • Book search actions in SearchBar (book_search_performed) [1] [2] [3]
  • Gated content dialog views and submissions (gated_content_viewed, gated_content_form_submitted) [1] [2] [3]
  • Contact form submissions (contact_form_submitted) [1] [2] [3]
  • Donation initiation (donation_initiated) [1] [2]

User Identification and Cohort Tagging:

• Automatically identifies and resets the user in PostHog on login/logout via a new PostHogUserIdentifier component in the application shell.
• Registers CMS-driven cohort properties (e.g., streamlined_nav) on all subsequent events for funnel analysis, using feature flags from the shared data context. [1] [2]

Feature Flag-Driven UI Experiments:

• Navigation menus now use PostHog feature flags to control the visibility and labeling of menu items, supporting A/B tests and gradual rollouts. This includes:
  • Passing feature flag values to menu item components to conditionally render or relabel nodes [1] [2]
  • New utility functions for flag-aware menu items and label swapping, e.g., for the "Products/Tools" dropdown

These changes lay the groundwork for robust analytics, experimentation, and user segmentation across the application.

[mwvolo]

@copilot resolve the merge conflicts in this pull request

[Copilot]

@copilot resolve the merge conflicts in this pull request

Merge conflicts resolved in commit e03cc92. The only conflict was test/src/contexts/streamlined-nav.test.tsx, which was deleted in main — I accepted that deletion to complete the merge.