TASK-031 TUI: Source status page (page 4)

Description

Add a 4th page accessible via 4 key showing a status table of all sources — useful for debugging stale data, misconfigured sources, and forced refreshes.

Columns: Kind | Enabled | Last Refreshed | Status (ok/error/unconfigured) | Error message (truncated)

Features:

• r on a selected row calls POST /api/sources/{id}/refresh to force-refresh that source
• Rows color-coded: green = ok, red = error, dim = disabled
• Auto-refreshes the table every 30s alongside the main data refresh
• Selected row shows full error in a detail area below the table

Implementation:

• Add ("page-status", "Status") to PAGES
• Add 4 binding
• Use DataTable widget for the table
• Fetch from existing /api/sources endpoint; all data already available

Acceptance Criteria

• #1 4 key switches to the Status page
• #2 Table shows all sources with kind, enabled state, last refresh time, and ok/error status
• #3 r on selected row triggers a force-refresh for that source
• #4 Error messages visible for failed sources
• #5 Page updates on the standard refresh interval