Add Activity and History page

[rroy676]

Goal

Add an arr-style Activity → History page that records important Stationarr events and makes troubleshooting easier.

Problem

Users currently need to inspect Docker logs or infer what happened from UI state. For real-world support, it would be useful to have an in-app event history showing playlist imports, refreshes, EPG fetches, scraper warnings, errors, and exports.

Arr ecosystem users expect an Activity/History area where past actions and failures can be reviewed.

Expected behaviour

Add a History page with entries such as:

2026-05-20 10:30 - Playlist refreshed - 80,000 channels
2026-05-20 10:32 - EPG fetched - 8,200 programmes
2026-05-20 10:35 - Scraper warning - ESPN2 tvtv.us returned 403
2026-05-20 10:40 - Export requested - playlist.m3u

History entries should include:

- timestamp
- event type
- status: success / warning / error / info
- title
- description/details
- related playlist/source/channel where applicable

Suggested event categories

- Playlist import
- Playlist refresh
- Playlist refresh failure
- EPG source fetch
- EPG fetch failure
- Scraper run
- Scraper warning / 0 programmes
- Generated playlist served/exported
- Update available
- Auth/admin/security events later

Requirements

• Keep history entries concise and useful.
• Avoid logging secrets, playlist URLs with tokens, API keys, or passwords.
• Add filtering by category/status.
• Add pagination for large histories.
• Consider automatic cleanup/retention later.

Validation

• Trigger a playlist refresh and confirm a history entry appears.
• Trigger an EPG fetch and confirm a history entry appears.
• Trigger an error condition and confirm it appears as warning/error.
• Confirm sensitive values are not exposed.

Related

Part of making Stationarr feel more native to the arr/self-hosted ecosystem. Related to System Tasks (#46), System Health (#45), and Logs page.