Show current EPG program on channel tiles

[fjordnode]

Summary

• Adds inline "now playing" EPG info on channel tiles for Xtream sources
• Uses the get_short_epg Xtream API to fetch the current program, with automatic fallback to get_simple_data_table when short EPG returns empty
• Displays the program title in blue below the channel name, replacing the source name when EPG data is available
• Requests are batched and run concurrently (capped at 10 parallel) to avoid blocking the UI or flooding the API

Screenshots

How it works

1. After the channel list loads, the frontend filters for Xtream livestream channels
2. Calls a new get_now_playing_batch Tauri command with those channels
3. Backend tries get_short_epg first for each stream, falls back to get_simple_data_table if empty
4. Decodes base64 titles and returns a map of channel ID → current program title
5. Channel tiles display the title when available, falling back to source name

Test plan

• Tested with Xtream source — EPG titles display correctly on channel tiles
• Fallback to full EPG works when short EPG returns empty
• Verify no regression on M3U-only sources (should show source name as before)

🤖 Generated with Claude Code

[CLAassistant]

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