feat: deploy WeekdayScaling to XAUUSD/USDJPY/GBPUSD

[cfournel]

Summary

Apply weekday lot-size scaling multipliers to 3 portfolio symbols after cross-year validation.

Winners (from dynamic_params_xv.csv)

Symbol	XV	Full PF Before	Full PF After	DD Δ
XAUUSD	3/4	2.60	2.86	flat
USDJPY	4/4	3.73	4.05	1.71% ↓
GBPUSD	4/4	1.81	1.98	1.67% ↓

EURJPY: no improvement — not applied.
ATRTP: failed all symbols — not applied.

Defaults applied (Tuesday=0.5×, Wednesday=0.75×, Friday=0.75×)

inpWeekdayScaling=true
inpWdMon=1.0, inpWdTue=0.5, inpWdWed=0.75, inpWdThu=1.0, inpWdFri=0.75

Done by

apply_dynamic_winners.py — auto-applied from dynamic_params_xv.csv

[cfournel]

Deployed via apply_dynamic_winners.py — XAUUSD/USDJPY/GBPUSD .set files updated with WeekdayScaling. Committed and pushed in commit 6dea136. ATRTP rejected (failed XV on all symbols).