FEAT-3: Wurf detail workspace (parents, juveniles, Jungtier erfassen prefill, expected Farbschlag via breed)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

gerbil-manager-web/src/pages/GerbilFormPage.tsx

@@ -1,5 +1,5 @@
 import { useState, type FormEvent } from 'react'
-import { Link, useNavigate, useParams } from 'react-router-dom'
+import { Link, useNavigate, useParams, useSearchParams } from 'react-router-dom'
 import { de } from '../strings/de'
 import { createGerbil, getGerbil, updateGerbil } from '../api/gerbils'
 import { listColorVarieties, listContacts, listEnclosures, listLitters } from '../api/lookups'
@@ -112,6 +112,22 @@ export default function GerbilFormPage() {
     setForm(formFromGerbil(existing.data))
   }
 
+  // Create-mode prefill from query params (?litterId, ?dob) — used by the Wurf
+  // workspace's "Jungtier erfassen" action to register a pup in one tap.
+  const [searchParams] = useSearchParams()
+  if (!isEdit && initializedFor === null) {
+    const litterId = searchParams.get('litterId')
+    const dob = searchParams.get('dob')
+    if (litterId || dob) {
+      setInitializedFor('new')
+      setForm((f) => ({
+        ...f,
+        litterId: litterId ?? f.litterId,
+        dateOfBirth: dob ?? f.dateOfBirth,
+      }))
+    }
+  }
+
   const set = <K extends keyof FormState>(key: K, value: FormState[K]) =>
     setForm((f) => ({ ...f, [key]: value }))