Show download progress on requests

[Quick104]

Silo-Server/silo-server#1643 adds download progress to requests in /api/v2. Today the phone and TV apps show a request's raw status as a badge or chip ("Queued", "Downloading"), and My Requests refreshes only on pull-to-refresh (phone) or the Refresh button (TV), so a requester can't tell how far along a download is.

What the server adds

All of it is additive.

• A RequestDownload object with:
  • phase: queued, downloading, paused, stalled, importing or import_blocked. Treat an unknown value as downloading.
  • percent: omitted while the size is unknown.
  • bytes_total, bytes_left, estimated_completion_at, downloads and updated_at.
• It appears in three places:
  • MediaRequest.download, which combines all of a request's downloads
  • RequestTarget.download
  • RequestMediaState.download on GET /api/v2/requests/detail/{media_type}/{tmdb_id}
• Capability: download_progress_supported on GET /api/v2/requests/status.

Work

• Decode download as optional on MediaRequest, RequestTarget and RequestState, and decode the capability on RequestsFeatureStatus. An unknown phase must still decode.
• Phone: a LinearProgressIndicator and "Downloading · 43% · about 12 min left", or the phase, in RequestListItem and on the request detail screen.
• TV: the same in TvRequestListCard and on the TV request detail screen.
• While My Requests or a request detail screen is visible and shows a request with download, reload every 30 seconds. Stop when nothing is downloading or the screen is no longer started.
• Hide the ETA when it has passed or updated_at is more than 10 minutes old.
• Tests: shared serialization with and without download, and the label and fraction formatting.

This builds on #401 (adopting request state) but doesn't depend on it: show progress whenever download is present. Request administration stays on the web.

Tracking: Silo-Server/silo-server#1643

AI disclosure

• Harness: T3 Code (Claude Code agent harness)
• Tool(s): Claude Code, GitHub CLI
• Model(s): claude-opus-5-5
• Involvement: AI-assisted; filed at the maintainer's request
• Adversarial review: n/a