Vest: stops reserve 0.02% of the position for slippage, not 0.1%

A platform may now state its own stop slippage share
(PlatformClient.stopSlippageFraction); the daily-loss reserve is the
larger of 10% of the limit and that share of the position. Vest's 9
measured stop-outs filled 0.9 points past the trigger on average and
2.25 at worst, against the ~30 points 0.1% held back. On a $1,400 day
with ~$495k of NDX the stop goes from ~$880 to ~$1,230, and the leg
sizes up for the same hold. Sizing, the placed stop, the dashboard's
next stop and the reset guard all use it; other platforms keep 0.1%.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

app/api/state/route.ts

@@ -176,7 +176,7 @@ export async function GET() {
                         // The reserve grows with the position (dllReserve): at
                         // the size the next leg would trade, where it's known.
                         const hard = dllRoom !== null && !lastStandNext
-                            ? dllStopDollars({ room: dllRoom, dailyLossLimit: dll, entryFee: 0, commissionPct: 0, notional: holdEstimate?.notional })
+                            ? dllStopDollars({ room: dllRoom, dailyLossLimit: dll, entryFee: 0, commissionPct: 0, notional: holdEstimate?.notional, slippageFraction: client.stopSlippageFraction })
                             : Infinity;
                         const stop = Math.min(Number.isFinite(obf) && obf > 0 ? obf : Infinity, hard);
                         if (Number.isFinite(stop) && stop > 0) nextStop = Math.round(stop * 100) / 100;