Optimize portable update_points DB path

[mateu]

What: Replace the portable (non-MySQL) update_points score rebuild loops with set-based SQL updates for region_score and player totals.

Why: /update_points spent most of its portable runtime in per-row DBIC loops (update_or_create + per-player updates), which does not scale with player count.

How: Keep the existing winner/lower-seed and round-out logic, then rebuild region_score in one INSERT ... SELECT over player x region with a left-joined aggregate of correct picks; recompute player.points in one SQL UPDATE from region_score sums.

Testing: script/test-env.sh prove -lv t/model_update_points.t and script/test-env.sh prove -lr t.

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Quality Report

Changes: 2 files changed, 62 insertions(+), 34 deletions(-)

Code scan: clean

Tests: skipped

Branch hygiene: clean

Generated by Kōan post-mission quality pipeline