feat(search): wrap search response in { documents, total } envelope

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/src/main/java/org/raddatz/familienarchiv/controller/DocumentController.java

@@ -12,6 +12,7 @@ import java.util.UUID;
 
 
 import io.swagger.v3.oas.annotations.Parameter;
+import org.raddatz.familienarchiv.dto.DocumentSearchResult;
 import org.raddatz.familienarchiv.dto.DocumentUpdateDTO;
 import org.raddatz.familienarchiv.dto.DocumentVersionSummary;
 import org.raddatz.familienarchiv.dto.IncompleteDocumentDTO;
@@ -187,7 +188,7 @@ public class DocumentController {
     }
 
     @GetMapping("/search")
-    public ResponseEntity<List<Document>> search(
+    public ResponseEntity<DocumentSearchResult> search(
             @RequestParam(required = false) String q,
             @RequestParam(required = false) LocalDate from,
             @RequestParam(required = false) LocalDate to,
@@ -198,7 +199,8 @@ public class DocumentController {
             @Parameter(description = "Filter by document status") @RequestParam(required = false) DocumentStatus status,
             @Parameter(description = "Sort field") @RequestParam(required = false) DocumentSort sort,
             @Parameter(description = "Sort direction: ASC or DESC") @RequestParam(required = false, defaultValue = "DESC") String dir) {
-        return ResponseEntity.ok(documentService.searchDocuments(q, from, to, senderId, receiverId, tags, tagQ, status, sort, dir));
+        List<Document> results = documentService.searchDocuments(q, from, to, senderId, receiverId, tags, tagQ, status, sort, dir);
+        return ResponseEntity.ok(DocumentSearchResult.of(results));
     }
 
     // --- VERSIONS ---

backend/src/main/java/org/raddatz/familienarchiv/dto/DocumentSearchResult.java

@@ -0,0 +1,11 @@
+package org.raddatz.familienarchiv.dto;
+
+import org.raddatz.familienarchiv.model.Document;
+
+import java.util.List;
+
+public record DocumentSearchResult(List<Document> documents, long total) {
+    public static DocumentSearchResult of(List<Document> documents) {
+        return new DocumentSearchResult(documents, documents.size());
+    }
+}

backend/src/test/java/org/raddatz/familienarchiv/controller/DocumentControllerTest.java

@@ -91,6 +91,18 @@ class DocumentControllerTest {
                 .andExpect(status().isBadRequest());
     }
 
+    @Test
+    @WithMockUser
+    void search_responseContainsTotalCount() throws Exception {
+        when(documentService.searchDocuments(any(), any(), any(), any(), any(), any(), any(), any(), any(), any()))
+                .thenReturn(Collections.emptyList());
+
+        mockMvc.perform(get("/api/documents/search"))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.total").value(0))
+                .andExpect(jsonPath("$.documents").isArray());
+    }
+
     // ─── POST /api/documents ─────────────────────────────────────────────────
 
     @Test