feat: add bot traffic filtering and engaged sessions metric to static analytics

[MillenniumFalconMechanic]

Ticket

Closes #4837

Summary

• Add regex-based suspicious page path filter to remove bot/malformed paths from the pageviews detail table (broken markdown links, CMS probes, asset requests, etc.)
• Add engagedSessions GA4 metric alongside sessions — displayed as "Engaged Sessions" in the stats card instead of "User Sessions"
• Export engaged_sessions in meta.json

Note

These changes affect all sites using the shared analytics package (AnVIL Portal, LungMAP, HCA Explorer, etc.)

Test plan

• Verify the generator runs successfully with the new metric
• Verify suspicious page paths are filtered from the pageviews table
• Verify the stats card shows "Engaged Sessions" with the correct count

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR updates the shared static analytics generator to reduce bot noise in pageview reports and surface GA4 engaged sessions as a primary stat.

Changes:

• Adds a suspicious page-path regex filter for pageviews.
• Fetches and exports GA4 engagedSessions.
• Updates the dashboard stats card from “User Sessions” to “Engaged Sessions.”

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
analytics/analytics_package/analytics/static_site/fetch.py	Adds suspicious path filtering and fetches engaged sessions.
analytics/analytics_package/analytics/static_site/export.py	Includes engaged sessions in meta.json.
analytics/analytics_package/analytics/static_site/template/index.html	Displays engaged sessions in the stats grid.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.