Merge branch 'worktree-agent-ae59040b377a324cb'

# Conflicts:
#	GerbilManagerWebAPI/ApplicationContext.cs
#	GerbilManagerWebAPI/Program.cs
#	gerbil-manager-web/e2e/mock-data.ts
#	gerbil-manager-web/src/pages/GerbilDetailPage.tsx
#	gerbil-manager-web/src/strings/de.ts

gerbil-manager-web/e2e/mock-api.ts

@@ -742,6 +742,59 @@ export async function installMockApi(page: Page): Promise<MockDb> {
       return json(route, 405)
     }
 
+    // EXHIBITION: Ausstellungs-/Show-Ergebnisse je Tier (POST/GET ?gerbilId=, PUT, DELETE).
+    // Plain-Liste (kein Gridify), gefiltert per ?gerbilId, neueste zuerst.
+    if (path === '/exhibitions') {
+      if (method === 'GET') {
+        const gerbilId = url.searchParams.get('gerbilId')
+        const rows = (db.exhibitions as Row[]).filter(
+          (r) => !gerbilId || r.gerbilId === gerbilId,
+        )
+        const sorted = [...rows].sort((a, b) =>
+          String(b.date ?? '').localeCompare(String(a.date ?? '')),
+        )
+        return json(route, 200, sorted)
+      }
+      if (method === 'POST') {
+        const body = request.postDataJSON() as Row
+        if (!String(body.eventName ?? '').trim())
+          return json(route, 400, 'EventName darf nicht leer sein.')
+        const created = {
+          id: newId('exhibition'),
+          gerbilId: body.gerbilId ?? null,
+          entityName: body.entityName ?? null,
+          eventName: String(body.eventName).trim(),
+          date: body.date ?? null,
+          placement: body.placement ?? null,
+          award: body.award ?? null,
+          note: body.note ?? null,
+          createdAt: new Date().toISOString(),
+        }
+        ;(db.exhibitions as Row[]).push(created)
+        return json(route, 201, created)
+      }
+      return json(route, 405)
+    }
+    const em = path.match(/^\/exhibitions\/([^/]+)$/)
+    if (em) {
+      const eid = decodeURIComponent(em[1])
+      const idx = (db.exhibitions as Row[]).findIndex((r) => r.id === eid)
+      if (idx < 0) return json(route, 404, { title: 'Not Found' })
+      if (method === 'GET') return json(route, 200, db.exhibitions[idx])
+      if (method === 'PUT') {
+        const body = request.postDataJSON() as Row
+        if ('eventName' in body && !String(body.eventName ?? '').trim())
+          return json(route, 400, 'EventName darf nicht leer sein.')
+        Object.assign(db.exhibitions[idx], body)
+        return json(route, 200, db.exhibitions[idx])
+      }
+      if (method === 'DELETE') {
+        ;(db.exhibitions as Row[]).splice(idx, 1)
+        return json(route, 204)
+      }
+      return json(route, 405)
+    }
+
     // Generische Kollektionen: /<resource> und /<resource>/<id>
     m = path.match(/^\/([a-z-]+)(?:\/([^/]+))?$/)
     const col = m ? collections[m[1]] : undefined