adjust dashboard berat page to match dashboard-cpsp

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;
@@ -69,7 +70,12 @@ export function getTargetWeightForAge(age: number, docWeight: number): number |
 /** Target daily weight gain (grams/day) for a given age from the standard. */
 export function getTargetGainForAge(age: number, docWeight: number): number | null {
   const values = pickStandardValues(docWeight);
-  if (age < 2 || age > values.length) return null;
+  if (age < 1 || age > values.length) return null;
+  if (age === 1) {
+    const current = values[0];
+    if (current == null || docWeight <= 0) return null;
+    return current - docWeight;
+  }
   const current = values[age - 1];
   const previous = values[age - 2];
   if (current == null || previous == null) return null;