526a40b01e
Renamed all "VIP N" to "Tier N" in config, server, and HTML dropdowns. Added recalc_equity_curve() that rebuilds the equity curve with new fee rates. Previously the equity curve was passed through unchanged when switching tiers, so the chart visually stayed identical even though PnL numbers changed. Now each tier produces its own curve. Example OBI historical: Tier 0 equity ends at 141.5, Tier 6 at 149.7 — the chart visibly shifts up as fees drop from 4.5bp to 2.4bp taker.