Live-match auto-scroll, transparent flag badges, reuse match card in tips modal

[kilgor-trout-c22]

Summary

• Competition view auto-scrolls to the last finished match right above a live match (one-shot guard so Pjax re-execution doesn't yank the viewport).
• Team flag badges drop their white background, removing the white box around flags on live match cards.
• "Show all tips" modal reuses the match card header (preview mode, footer omitted) instead of a separate pairing/result line; the card sits in a fixed sub-header pinned above the scrollable body. Title bar reads "All placed tips".

Notes

• _match_card.php gains an optional preview flag that renders only the part above the dashed footer line.
• CHANGELOG updated under 1.0.9 (Unreleased); module.json version not bumped (unreleased convention).