Add explicit per-plan gauge temperature offset

shared/curve.js

@@ -9,11 +9,14 @@ const numeric = (v) =>
     ? Number(v)
     : null;
 
-// No roaster selection, learned median, or override changes these illustrative points.
+// An explicit per-plan gauge offset is a temperature difference: no +32 conversion.
+// Legacy roaster selection, learned medians, and machine overrides remain ignored.
+export const planTemperatureOffsetF = (plan) => numeric(plan?.temperatureOffsetF) ?? 0;
 export function buildPlanCurve(plan, ledger) {
   const t = plan.temps ?? {};
-  const fc = numeric(t.fc?.tempC) ?? 200;
-  const yellow = numeric(t.yellow?.tempC) ?? 160;
+  const offsetC = planTemperatureOffsetF(plan) / 1.8;
+  const fc = numeric(t.fc?.tempC) ?? (200 + offsetC);
+  const yellow = numeric(t.yellow?.tempC) ?? (160 + offsetC);
   const maillardRate =
     ledger.maillard > 0 ? Math.max(0, (fc - yellow) / ledger.maillard) : 0;
   // Development's mean rise is lower than Maillard's, even for a short development.
@@ -23,13 +26,13 @@ export function buildPlanCurve(plan, ledger) {
       key: "charge",
       label: "Charge",
       timeS: 0,
-      tempC: numeric(t.charge?.tempC) ?? 200,
+      tempC: numeric(t.charge?.tempC) ?? (200 + offsetC),
     },
     {
       key: "tp",
       label: "Turning point",
       timeS: t.tp?.time ? parseDuration(t.tp.time) : 60,
-      tempC: numeric(t.tp?.tempC) ?? 95,
+      tempC: numeric(t.tp?.tempC) ?? (95 + offsetC),
     },
     {
       key: "yellow",