Dashboard Cards: Activity Card implement tracking

[zwarm]

Closes #18219

This PR adds tracks events for Activity Card:

• my_site_dashboard_card_shown - when the Activity card is shown
• my_site_dashboard_card_item_tapped - when an Activity log item is tapped within the card
• my_site_dashboard_card_footer_action_tapped - when the activity card footer link is tapped

Merge Instructions

• Ensure that Dashboard Cards: Activity Card implement onclick behavior #18306 has been merged
• Remove Not Ready for Merge Label
• Merge as normal

cc: @startuptester - testing milestone

To test:

1. Install the Jetpack app
2. Login with a wp account
3. Select a site in which you can access the activity log (manage content/admin)
4. Navigate to App Settings > Privacy Settings
5. Enable Collect Information
6. Navigate to back App Settings > Debug Settings
7. Enable dashboard_card_activity_log and restart the app
8. Navigate to Home
9. ✅ Verify logs contain: 🔵 Tracked: my_site_dashboard_card_shown, Properties: {"type":"activity_log","subtype":"activity_log"}
10. Locate the Activity Card and tap on the "View all activity" footer link
11. ✅ Verify logs contain: 🔵 Tracked: my_site_dashboard_card_footer_action_tapped, Properties: {"type":"activity_log","subtype":"activity_log"}
12. Navigate back to Home
13. Locate the Activity Card and tap on an activity log item row
14. ✅ Verify logs contain: 🔵 Tracked: my_site_dashboard_card_item_tapped, Properties: {"type":"activity_log","subtype":"activity_log"}

Regression Notes

1. Potential unintended areas of impact
   Events are not tracked

2. What I did to test those areas of impact (or what existing automated tests I relied on)
   Manual and unit tests

3. What automated tests I added (or what prevented me from doing so)
   Added tests to CardsTrackerTest and CardsShownTrackerTest

PR submission checklist:

• I have completed the Regression Notes.
• I have considered adding accessibility improvements for my changes.
• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.

[wpmobilebot]

📲 You can test the changes from this Pull Request in WordPress by scanning the QR code below to install the corresponding build.

	App Name	WordPress
	Flavor	Jalapeno
	Build Type	Debug
	Version	pr18310-3bb31a6
	Commit	3bb31a6
	Direct Download	wordpress-prototype-build-pr18310-3bb31a6.apk

Note: Google Login is not supported on these builds.

[wpmobilebot]

📲 You can test the changes from this Pull Request in Jetpack by scanning the QR code below to install the corresponding build.

	App Name	Jetpack
	Flavor	Jalapeno
	Build Type	Debug
	Version	pr18310-3bb31a6
	Commit	3bb31a6
	Direct Download	jetpack-prototype-build-pr18310-3bb31a6.apk

Note: Google Login is not supported on these builds.

[AjeshRPai]

Hey @zwarm

I have tested all the tracking events. Everything looks good to me. Also the unit tests look fine to me.

Once the CI is successful, I will merge the PR.