M3U Sources: a * entry stands for every other source

[PiratesIRC]

What was wrong

A user wanted streams from one free provider first and any other provider when the free one has nothing, without naming every provider. Naming only the free provider made Match and Assign use only that provider: in Match and Assign and Preview the M3U Sources list filters as well as sets the order. Listing every provider works until a new provider is added and the list is not updated.

What this changes

• A * entry in M3U Sources stands for every source not named. No source is dropped. Named sources rank in the order written and every other source takes the position of the *:
  • Free Provider, *: Free Provider first, every other source after it, including ones added later.
  • *, Backup: every other source first, Backup last.
• A list without * behaves as before: Match and Assign and Preview use only the listed sources, and Sort Alternate Streams ranks unlisted sources last.
• _resolve_m3u_priorities is now the one reader of the setting, used by the load path (Match and Assign, Preview) and by Sort Alternate Streams.
• A source named twice keeps its first position (before, a repeat moved it to its last position). Names that match no account are logged, and the Sort log no longer gives them a priority number.
• Help text, the README settings row and the CSV header describe the wildcard.

Testing

• New tests/test_m3u_source_wildcard.py (16 tests), including an end-to-end check through _sort_streams_by_quality. The full suite passes (1562).
• Ignoring the wildcard, ranking it last, keeping a repeat at its last position, and Sort ignoring the wildcard each make at least one test fail.
• The workspace release gate passes all 9 gates on this branch. An independent review compared old and new code for lists without * (unknown names, streams with no source, the "none found" fallback) and found no change in behaviour.

🤖 Generated with Claude Code