feat: the work view and the Managed files panel

[pacphi]

Why

The landing page replaces the machine summary (design: The work view).

In scope

Activity, Hosts, Places, Most active unmanaged places, Health, Needs attention, Versions in use, Codex exceptions, Cache, Learning and Footprint cards; per-place detail; the Managed files panel.

Out of scope

Writes.

Acceptance criteria

• Every card follows the scope filter
• Unmanaged places offer ak init where the kind allows

Dependencies

Blocked by: #366, #367, #368

Blocks: #377, #388, #411

Plan

• Release: 4.0.0-beta.4
• Size: size:M · Workstream: ws:project-scope
• Epic: feat: project-scope P6, the dashboard for all work (epic) #301
• Card: P6-08 in the card inventory
• Sources: Design (docs(plans): project-scoped management design and its prerequisites #289) The work view

Verification

• pnpm run test:ui