Envision activity hierarchy rendering on Activity detail pages

[JayVDZ]

Summary

Activity records support parent/child relationships via the ParentActivityId property. Currently, the Activity list filters out child activities (those with ParentActivityId != null), but there's no visual representation of this hierarchy on the Activity detail pages or list.

Background

When certain operations trigger sub-operations, child activities are created and linked to a parent. For example:

• Export operations that auto-create containers spawn a child "Connected System Update" activity for the container auto-selection process
• Future operations may also create nested activities

The relationship exists in the data model but isn't surfaced in the UI.

Scope

This issue is for envisioning and solutioning - exploring options for how activity hierarchy could be rendered, not prescribing a specific implementation.

Questions to Answer

1. Where should hierarchy be shown?

   • Activity detail page only?
   • Activity list with expand/collapse?
   • Both?

2. How should child activities be rendered?

   • Nested accordion/expansion panels
   • Timeline view with indentation
   • Tree view component
   • Tabs (Parent | Children)
   • Inline summary with "View children" link

3. What information should be visible?

   • Full child activity details inline?
   • Summary cards that link to child detail pages?
   • Aggregated status (e.g., "3 child activities: 2 complete, 1 in progress")

4. How should the Activity list indicate children?

   • Badge/chip showing child count (e.g., "+3 sub-activities")
   • Icon indicator that can be expanded
   • Tooltip on hover showing child summary
   • Column showing child count

5. MudBlazor component options to evaluate:

   • MudExpansionPanels - for collapsible sections
   • MudTreeView - for hierarchical data
   • MudTimeline - for sequential/nested operations
   • MudList with custom nesting
   • MudTabs - for separating parent/child views
   • MudBadge or MudChip - for child count indicators on list

Tasks

• Confirm API supports retrieving child activities by parent ID
• Confirm PowerShell module exposes parent/child relationship data
• Add child activity count to Activity list query/DTO
• Update Activity list page to show indicator for activities with children
• Review MudBlazor components for hierarchy rendering options
• Create mockups or wireframes for 2-3 approaches
• Select preferred approach based on UX and implementation complexity
• Implement chosen solution for Activity detail page

Related

• Activity model: JIM.Models/Activities/Activity.cs (has ParentActivityId property)
• Activity repository already filters by ParentActivityId == null for top-level list
• Recent fix linked container auto-selection activity as child of export activity (commit a7301f5)

Acceptance Criteria

• Activity list shows indicator when an activity has child activities (with count)
• Users can see when an activity has child activities on the detail page
• Users can navigate to/view child activity details
• Hierarchy is intuitive and doesn't clutter the UI for activities without children

[JayVDZ]

Also evaluate Timeline: https://mudblazor.com/components/timeline#basic