[krtschil]

Summary

• Convert Individual DAT tournaments with all four player numbers and seat-specific matchpoints to JSON, USEBIO XML and PBN.
• Add a shared player ranking and per-player analysis with changing partners, opponents and automatic seat/role detection.
• Improve scorecard readability with row separators and opponent seat labels instead of player numbers.

Verification

• Repository regression suite passed after implementing Individual support; targeted display regressions passed after the readability refinement.
• All 20 official scores and percentages in export2181.dat match the stored individual matchpoint sums.
• Browser checks covered JSON/XML loading, all 20 scorecards and player selection from traveller results.
• User tested develop and approved merging.