Late move reduction

[fatorius]

Ajustes em LMR

Results of candidate vs baseline (10+0.1, 1t, 256MB, UHO_Lichess_4852_v1.epd):
Elo: 81.91 +/- 19.57, nElo: 107.65 +/- 24.77
LOS: 100.00 %, DrawRatio: 35.19 %, PairsRatio: 2.95
Games: 756, Wins: 342, Losses: 167, Draws: 247, Points: 465.5 (61.57 %)
Ptnml(0-2): [16, 46, 133, 113, 70], WL/DD Ratio: 2.02
LLR: 2.97 (100.8%) (-2.94, 2.94) [0.00, 5.00]

[Copilot]

Pull request overview

Replaces the previous score-bucket-based depth reduction scheme in the main search with a classical logarithmic Late Move Reduction (LMR) formula for late quiet moves in non-PV nodes, and updates the copyright year in the startup banners. STC SPRT results show a strong Elo gain (+81.9 ± 19.6).

Changes:

• Restructures the extensions/reductions block in Search::pesquisa into explicit branches (check extension, no-reduce for first move / good captures, LMR for late quiet moves at depth ≥ 3, otherwise depth-1) and computes lmr_r = log(d) * log(i) / 2.
• Adds the LMR re-search at profundidade - 1 (full depth) when the scout search exceeds alpha.
• Bumps the banner year from 2023 to 2026 in main.cpp, unit_tests.cpp, and bench_tests.cpp, and includes <math.h> in search.cpp for log().

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
src/search.cpp	New LMR formula and restructured extensions/reductions; full-depth re-search after scout fails high.
src/main.cpp	Updates the startup banner year to 2026.
src/unit_tests.cpp	Updates the unit test banner year to 2026.
src/bench_tests.cpp	Updates the bench banner year to 2026.

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