Show all your groups on the Your groups tab, not just the first page

[edwh]

Fixes #928.

Summary

• Before: on the Your groups tab, someone who follows a lot of groups saw only the first page (around 20–25, A to H for Florine). Scrolling down loaded no more.
• Why: the tab fetches each of your groups separately. The list loads more rows as you scroll, but it checked before most of the groups had arrived. It found nothing more to show, stopped, and never checked again.
• After: the list starts checking again whenever more groups arrive, or when the groups in view change on the map. Scrolling down now reaches all your groups.

Code Quality Review

• One small change in GroupsTable.vue: the scroller gets an identifier that changes when more groups arrive. This is the documented way to restart vue-infinite-loading.
• The map tab uses the same table and gets the same fix. Before, zooming out after the list had already ended could also leave groups unreachable.

Test Plan

• New jest test: groups that arrive after the scroller has stopped can still be scrolled to. It fails without the fix and passes with it.
• Full jest suite passes (166 tests).
• Checked on the preview with an account in 60 groups: scrolling down shows all 60.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

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