[dajiaohuang]

Fixes #201.

docs/CLI.md told agents that --mock exposes the full MatchDetails shape "(events, lineups, stats, formations)" and recommended mock IDs for validating a lineup jq pipeline. The bundled mocks do not carry those fields:

$ golazo match 2001 --mock | jq '.data[0] | {home_starting, home_lineup, home_formation}'
{
  "home_starting": null,
  "home_lineup": null,
  "home_formation": null
}

internal/data/mock_details.go adds only Events, Statistics, Venue, Referee and Attendance to the embedded Match; the same holds for the away side and for every bundled ID (2002-2005, 1001-1012). display_minute is also only populated on some bundled events (2004/2005) while the documented event schema lists it unconditionally.

The change is limited to docs/CLI.md:

• the quick-start sentence no longer offers mock lineups;
• the Known-limitations bullet now says exactly which fields mock details cover, which ones they omit, and that lineup/formation validation must happen against real matches in the TUI.

Verified by re-reading both edited paragraphs and checking the claims against the built binary (golazo match <id> --mock for 2001-2005 and 1001-1012). No code or schema changes.