feat(persons): add notes field to person profile (issue #23)

V5 Flyway migration adds TEXT notes column; Person entity, service, and
controller updated to persist notes. Frontend edit form adds textarea and
view mode renders the notes section. Backed by 2 new service unit tests
(persist + blank clears).

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

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

@@ -55,7 +55,7 @@ public class PersonController {
         if (firstName == null || firstName.isBlank() || lastName == null || lastName.isBlank()) {
             throw new ResponseStatusException(HttpStatus.BAD_REQUEST, "Vor- und Nachname sind Pflichtfelder");
         }
-        return ResponseEntity.ok(personService.updatePerson(id, firstName.trim(), lastName.trim(), body.get("alias")));
+        return ResponseEntity.ok(personService.updatePerson(id, firstName.trim(), lastName.trim(), body.get("alias"), body.get("notes")));
     }
 
     @PostMapping("/{id}/merge")

backend/src/main/java/org/raddatz/familienarchiv/model/Person.java

@@ -28,4 +28,8 @@ public class Person {
 
     // Optional: Aliasse für die Suche (z.B. "Opa Hans")
     private String alias;
+
+    // Optional: Free-text biographical notes
+    @Column(columnDefinition = "TEXT")
+    private String notes;
 }

backend/src/main/java/org/raddatz/familienarchiv/service/PersonService.java

@@ -58,12 +58,13 @@ public class PersonService {
     }
 
     @Transactional
-    public Person updatePerson(UUID id, String firstName, String lastName, String alias) {
+    public Person updatePerson(UUID id, String firstName, String lastName, String alias, String notes) {
         Person person = personRepository.findById(id)
                 .orElseThrow(() -> new ResponseStatusException(HttpStatus.NOT_FOUND, "Person nicht gefunden"));
         person.setFirstName(firstName);
         person.setLastName(lastName);
         person.setAlias(alias == null || alias.isBlank() ? null : alias.trim());
+        person.setNotes(notes == null || notes.isBlank() ? null : notes.trim());
         return personRepository.save(person);
     }
 

backend/src/main/resources/db/migration/V5__add_notes_to_persons.sql

@@ -0,0 +1 @@
+ALTER TABLE persons ADD COLUMN notes TEXT;