fix(document): fix test assertion structure + add entity graph decision comments

- Refactor DocumentLazyLoadingTest: pull value assertions (assertThat) out
  of assertThatCode lambdas so failures surface as AssertionError rather
  than "unexpected exception: AssertionError" (review item 1)
- Add @EntityGraph("Document.full") to findBySenderId, findByReceiversId,
  findConversation, and findSinglePersonCorrespondence — all return full
  Documents to the controller for JSON serialization (review item 2)
- Add "// Callers access only ..." comments to un-graphed methods where no
  lazy associations are touched: findByTags_Id, findByStatus,
  findByMetadataCompleteFalse(Sort), findByMetadataCompleteFalse(Pageable)
- Remove "what" inline comments from @Transactional(readOnly=true)
  on getRecentActivity and getDocumentById — the why is in ADR-022 (item 4)
- Add named-graph coupling consequence to ADR-022: Document.java and
  DocumentRepository.java graph name strings must stay in sync (item 5)

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

backend/src/main/java/org/raddatz/familienarchiv/document/DocumentRepository.java

@@ -44,17 +44,19 @@ public interface DocumentRepository extends JpaRepository<Document, UUID>, JpaSp
     // Wie oben, gibt aber nur das erste Ergebnis zurück — sicher wenn doppelte Dateinamen existieren
     Optional<Document> findFirstByOriginalFilename(String originalFilename);
 
-    // Findet alle Dokumente mit einem bestimmten Status
+    // Callers access only status/id scalar fields — no graph needed.
-    // z.B. um alle offenen "PLACEHOLDER" zu finden
     List<Document> findByStatus(DocumentStatus status);
 
     // Prüft effizient, ob ein Dateiname schon existiert (gibt true/false zurück)
     boolean existsByOriginalFilename(String originalFilename);
 
+    @EntityGraph("Document.full")
     List<Document> findBySenderId(UUID senderId);
 
+    @EntityGraph("Document.full")
     List<Document> findByReceiversId(UUID receiverId);
 
+    // Callers access only doc.getTags() to mutate the set — receivers/sender not touched; no graph needed.
     List<Document> findByTags_Id(UUID tagId);
 
     @Query("SELECT d FROM Document d WHERE d.id NOT IN (SELECT DISTINCT dv.documentId FROM DocumentVersion dv)")
@@ -69,12 +71,15 @@ public interface DocumentRepository extends JpaRepository<Document, UUID>, JpaSp
 
     long countByMetadataCompleteFalse();
 
+    // No production callers — only used if a future export path iterates the full list; no graph needed.
     List<Document> findByMetadataCompleteFalse(Sort sort);
 
+    // Callers map to IncompleteDocumentDTO using only scalar fields (id, title, createdAt) — no graph needed.
     Page<Document> findByMetadataCompleteFalse(Pageable pageable);
 
     Optional<Document> findFirstByMetadataCompleteFalseAndIdNot(UUID id, Sort sort);
 
+    @EntityGraph("Document.full")
     @Query("SELECT DISTINCT d FROM Document d " +
             "JOIN d.receivers r " +
             "WHERE " +
@@ -89,6 +94,7 @@ public interface DocumentRepository extends JpaRepository<Document, UUID>, JpaSp
             @Param("to") LocalDate to,
             Sort sort);
 
+    @EntityGraph("Document.full")
     @Query("SELECT DISTINCT d FROM Document d " +
             "LEFT JOIN d.receivers r " +
             "WHERE (d.sender.id = :personId OR r.id = :personId) " +

backend/src/main/java/org/raddatz/familienarchiv/document/DocumentService.java

@@ -636,8 +636,6 @@ public class DocumentService {
         return saved;
     }
 
-    // @Transactional(readOnly=true) keeps the Hibernate session open so the
-    // lazy-loaded sender and tags on returned documents remain accessible to callers.
     @Transactional(readOnly = true)
     public List<Document> getRecentActivity(int size) {
         return documentRepository.findAll(
@@ -846,8 +844,6 @@ public class DocumentService {
         documentRepository.save(doc);
     }
 
-    // @Transactional(readOnly=true) keeps the Hibernate session open so the
-    // lazy-loaded tags and receivers on the returned document remain accessible to callers.
     @Transactional(readOnly = true)
     public Document getDocumentById(UUID id) {
         Document doc = documentRepository.findById(id)

backend/src/test/java/org/raddatz/familienarchiv/document/DocumentLazyLoadingTest.java

@@ -70,12 +70,16 @@ class DocumentLazyLoadingTest {
 
         Document result = documentService.getDocumentById(doc.getId());
 
+        // Only the collection access itself is in assertThatCode — guards against LazyInitializationException.
+        // Value assertions live outside so failures surface as AssertionError, not as unexpected exception.
         assertThatCode(() -> {
-            assertThat(result.getTags()).isNotEmpty();
+            result.getTags().size();
-            result.getTags().forEach(t -> assertThat(t.getName()).isNotNull());
+            result.getReceivers().size();
-            assertThat(result.getReceivers()).isNotEmpty();
-            result.getReceivers().forEach(r -> assertThat(r.getLastName()).isNotNull());
         }).doesNotThrowAnyException();
+        assertThat(result.getTags()).isNotEmpty();
+        result.getTags().forEach(t -> assertThat(t.getName()).isNotNull());
+        assertThat(result.getReceivers()).isNotEmpty();
+        result.getReceivers().forEach(r -> assertThat(r.getLastName()).isNotNull());
     }
 
     @Test
@@ -88,11 +92,14 @@ class DocumentLazyLoadingTest {
 
         List<Document> results = documentService.getRecentActivity(3);
 
+        // Access lazy fields inside assertThatCode — guards against LazyInitializationException.
+        // Value assertions live outside so failures surface as AssertionError, not as unexpected exception.
         assertThatCode(() -> {
-            results.forEach(d -> assertThat(d.getSender()).isNotNull());
+            results.forEach(d -> d.getSender().getLastName());
-            results.forEach(d -> assertThat(d.getSender().getLastName()).isNotNull());
             results.forEach(d -> d.getTags().size());
         }).doesNotThrowAnyException();
+        results.forEach(d -> assertThat(d.getSender()).isNotNull());
+        results.forEach(d -> assertThat(d.getSender().getLastName()).isNotNull());
     }
 
     @Test

docs/adr/022-eager-to-lazy-fetch-strategy.md

@@ -102,3 +102,9 @@ open long enough for the caller to use the result."
   `Person` and `Tag` carry this annotation to prevent Jackson from attempting to serialize
   Hibernate proxy internals when the association is not initialized. Any new entity that is
   used as a lazy association and serialized directly (without a DTO) needs the same annotation.
+- **Named graph strings in `Document.java` and `DocumentRepository.java` must stay in sync.**
+  The `@NamedEntityGraph(name = "Document.full")` / `@NamedEntityGraph(name = "Document.list")`
+  definitions on `Document` are referenced by string in every `@EntityGraph(value = "...")` on
+  `DocumentRepository`. If the names diverge (e.g. a graph is renamed in one place but not the
+  other), Spring Data throws at application startup. Always update both files together when
+  renaming or restructuring a named graph.