test(importing): clean up committed rows after CanonicalImportIntegrationTest

The canonical importer commits through its own transactions, so this test
cannot use @Transactional rollback for isolation. Without cleanup, the last
test's committed documents (dated 1888-02), persons and tags leaked into the
shared Testcontainers Postgres and polluted other integration tests that
assume a known seed (DocumentDensityIntegrationTest got an extra 1888-02
bucket; DocumentSearchPagedIntegrationTest counted 122 docs instead of 120).

Add an @AfterEach deleteAll of documents/persons/tags, matching the existing
convention in DocumentListItemIntegrationTest.

Refs #669

backend/src/test/java/org/raddatz/familienarchiv/importing/CanonicalImportIntegrationTest.java

@@ -3,6 +3,7 @@ package org.raddatz.familienarchiv.importing;
 import org.apache.poi.ss.usermodel.Row;
 import org.apache.poi.ss.usermodel.Sheet;
 import org.apache.poi.xssf.usermodel.XSSFWorkbook;
+import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.raddatz.familienarchiv.PostgresContainerConfig;
@@ -59,6 +60,22 @@ class CanonicalImportIntegrationTest {
         ReflectionTestUtils.setField(orchestrator, "canonicalDir", artifactDir.toString());
     }
 
+    /**
+     * The import commits through its own transactions (the orchestrator is not transactional),
+     * so this test cannot rely on {@code @Transactional} rollback for isolation. Delete the
+     * committed rows after each test — otherwise the last test's documents (dated 1888-02) and
+     * persons/tags leak into the shared Testcontainers Postgres and pollute other integration
+     * tests that assume a known seed (e.g. DocumentDensityIntegrationTest,
+     * DocumentSearchPagedIntegrationTest). Mirrors the @AfterEach deleteAll convention used by
+     * DocumentListItemIntegrationTest.
+     */
+    @AfterEach
+    void cleanup() {
+        documentRepository.deleteAll();
+        personRepository.deleteAll();
+        tagRepository.deleteAll();
+    }
+
     @Test
     void reimport_isIdempotent_noDuplicatePersonsTagsOrDocuments() {
         orchestrator.runImport();