fix day 0 insight main dashboard page

utils/weight.ts

@@ -61,6 +61,7 @@ function pickStandardValues(docWeight: number): number[] {
 
 /** Target body weight (grams) for a given age from the Ross 308 DOC-weight table. */
 export function getTargetWeightForAge(age: number, docWeight: number): number | null {
+  if (age === 0) return docWeight > 0 ? docWeight : null;
   const values = pickStandardValues(docWeight);
   if (age < 1 || age > values.length) return null;
   return values[age - 1] ?? null;