feat(parser): implement stripTitle for known prefixes

Two-pass title stripping with loop for stacked titles:
- Dot-prefixes (Dr., Prof.) matched without trailing space
- Word-prefixes (Tante, Frau, Schwester, etc.) matched at
  word boundary
- Stacked titles like "Prof. Dr. Muller" handled correctly
- Single token after title strip goes to lastName (not firstName)

Add 5 "von" last names to KNOWN_LAST_NAMES for correct splitting
of entries like "Freifrau von Massenbach".

15 new test cases + updated 3 existing tests for title behavior.

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

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

@@ -16,6 +16,7 @@ public class PersonNameParser {
     // Known last names in this archive, longest first to avoid partial matches
     // (e.g. "de Gruyter" must be checked before any single-word name)
     static final List<String> KNOWN_LAST_NAMES = List.of(
+            "von der Heide", "von Massenbach", "von Geldern", "von Gelden", "von Staa",
             "de Gruyter", "Dieckmann", "Gruber", "Müller", "Wolff", "Cram");
 
     private static final Pattern GEB_PATTERN = Pattern.compile(",?\\s*geb\\.?\\s+(.+)$");
@@ -149,8 +150,22 @@ public class PersonNameParser {
 
         NameParts parts = splitByKnownLastNameOrFallback(cleaned);
 
+        String firstName = parts.firstName();
+        String lastName = parts.lastName();
+
+        // When a title was stripped and no first name could be extracted, the
+        // remaining text is the lastName. "Tante Molly" -> title=Tante, lastName=Molly.
+        if (title.title() != null) {
+            if ("?".equals(lastName) && !cleaned.contains(" ")) {
+                lastName = firstName;
+                firstName = null;
+            } else if (firstName.equals(lastName)) {
+                firstName = null;
+            }
+        }
+
         return new SplitName(
-                title.title(), parts.firstName(), parts.lastName(),
+                title.title(), firstName, lastName,
                 maiden.maidenName(), paren.annotation()
         );
     }
@@ -196,9 +211,50 @@ public class PersonNameParser {
         return new AnnotationResult(cleaned, rawAnnotation);
     }
 
-    /** Strips title prefixes. Pass-through until #212. */
+    private static final List<String> DOT_PREFIXES = List.of("Dr.", "Prof.");
+
+    private static final List<String> WORD_PREFIXES = List.of(
+            "Frau", "Herr", "Freifrau", "Freiherr",
+            "Tante", "Onkel", "Schwester", "Bruder",
+            "Cousine", "Cousin", "Freundin", "Freund",
+            "Mutter", "Vater", "Pastor", "Architekt");
+
+    /** Strips known title/relationship prefixes, looping for stacked titles. */
     public static TitleResult stripTitle(String input) {
-        return new TitleResult(input, null);
+        String remaining = input;
+        StringBuilder titleBuilder = new StringBuilder();
+        boolean found = true;
+
+        while (found) {
+            found = false;
+
+            for (String prefix : DOT_PREFIXES) {
+                if (remaining.toLowerCase().startsWith(prefix.toLowerCase())) {
+                    titleBuilder.append(titleBuilder.isEmpty() ? "" : " ").append(prefix);
+                    remaining = remaining.substring(prefix.length()).trim();
+                    found = true;
+                    break;
+                }
+            }
+            if (found) continue;
+
+            for (String prefix : WORD_PREFIXES) {
+                String lower = remaining.toLowerCase();
+                if (lower.startsWith(prefix.toLowerCase() + " ") || lower.equals(prefix.toLowerCase())) {
+                    titleBuilder.append(titleBuilder.isEmpty() ? "" : " ").append(prefix);
+                    remaining = remaining.length() > prefix.length()
+                            ? remaining.substring(prefix.length() + 1).trim()
+                            : "";
+                    found = true;
+                    break;
+                }
+            }
+        }
+
+        if (titleBuilder.isEmpty()) {
+            return new TitleResult(input, null);
+        }
+        return new TitleResult(remaining, titleBuilder.toString());
     }
 
     /** Splits a cleaned name into firstName/lastName using known last names or last-space fallback. */

backend/src/test/java/org/raddatz/familienarchiv/service/PersonNameParserTest.java

@@ -190,14 +190,16 @@ class PersonNameParserTest {
     @Test
     void split_dotCompressed_titleFirstNameLastName() {
         PersonNameParser.SplitName result = PersonNameParser.split("Dr.Fr.Zarncke");
-        assertThat(result.firstName()).isEqualTo("Dr. Fr.");
+        assertThat(result.title()).isEqualTo("Dr.");
+        assertThat(result.firstName()).isEqualTo("Fr.");
         assertThat(result.lastName()).isEqualTo("Zarncke");
     }
 
     @Test
     void split_dotCompressed_titleAndLastName() {
         PersonNameParser.SplitName result = PersonNameParser.split("Dr.Zarnke");
-        assertThat(result.firstName()).isEqualTo("Dr.");
+        assertThat(result.title()).isEqualTo("Dr.");
+        assertThat(result.firstName()).isNull();
         assertThat(result.lastName()).isEqualTo("Zarnke");
     }
 
@@ -210,7 +212,8 @@ class PersonNameParserTest {
     @Test
     void split_alreadySpacedDotName_noDoubleSpacing() {
         PersonNameParser.SplitName result = PersonNameParser.split("Dr. Fr. Zarncke");
-        assertThat(result.firstName()).isEqualTo("Dr. Fr.");
+        assertThat(result.title()).isEqualTo("Dr.");
+        assertThat(result.firstName()).isEqualTo("Fr.");
         assertThat(result.lastName()).isEqualTo("Zarncke");
     }
 
@@ -353,12 +356,112 @@ class PersonNameParserTest {
     }
 
     @Test
-    void stripTitle_isPassthrough() {
+    void stripTitle_noPrefix_returnsNull() {
         PersonNameParser.TitleResult result = PersonNameParser.stripTitle("Walter de Gruyter");
         assertThat(result.cleaned()).isEqualTo("Walter de Gruyter");
         assertThat(result.title()).isNull();
     }
 
+    @Test
+    void stripTitle_tante() {
+        PersonNameParser.TitleResult result = PersonNameParser.stripTitle("Tante Molly");
+        assertThat(result.cleaned()).isEqualTo("Molly");
+        assertThat(result.title()).isEqualTo("Tante");
+    }
+
+    @Test
+    void stripTitle_schwester() {
+        PersonNameParser.TitleResult result = PersonNameParser.stripTitle("Schwester Hanni");
+        assertThat(result.cleaned()).isEqualTo("Hanni");
+        assertThat(result.title()).isEqualTo("Schwester");
+    }
+
+    @Test
+    void stripTitle_frau() {
+        PersonNameParser.TitleResult result = PersonNameParser.stripTitle("Frau Bakker");
+        assertThat(result.cleaned()).isEqualTo("Bakker");
+        assertThat(result.title()).isEqualTo("Frau");
+    }
+
+    @Test
+    void stripTitle_cousine_withFullName() {
+        PersonNameParser.TitleResult result = PersonNameParser.stripTitle("Cousine Emmy Haniel");
+        assertThat(result.cleaned()).isEqualTo("Emmy Haniel");
+        assertThat(result.title()).isEqualTo("Cousine");
+    }
+
+    @Test
+    void stripTitle_freifrau() {
+        PersonNameParser.TitleResult result = PersonNameParser.stripTitle("Freifrau von Massenbach");
+        assertThat(result.cleaned()).isEqualTo("von Massenbach");
+        assertThat(result.title()).isEqualTo("Freifrau");
+    }
+
+    @Test
+    void stripTitle_dotPrefix_withSpace() {
+        PersonNameParser.TitleResult result = PersonNameParser.stripTitle("Dr. Sattelmacher");
+        assertThat(result.cleaned()).isEqualTo("Sattelmacher");
+        assertThat(result.title()).isEqualTo("Dr.");
+    }
+
+    @Test
+    void stripTitle_dotPrefix_noSpace() {
+        PersonNameParser.TitleResult result = PersonNameParser.stripTitle("Dr.von Gelden");
+        assertThat(result.cleaned()).isEqualTo("von Gelden");
+        assertThat(result.title()).isEqualTo("Dr.");
+    }
+
+    @Test
+    void stripTitle_stacked_profDr() {
+        PersonNameParser.TitleResult result = PersonNameParser.stripTitle("Prof. Dr. Muller");
+        assertThat(result.cleaned()).isEqualTo("Muller");
+        assertThat(result.title()).isEqualTo("Prof. Dr.");
+    }
+
+    // --- split — title extraction end-to-end ---
+
+    @Test
+    void split_tante_setsTitle_firstNameNull() {
+        PersonNameParser.SplitName result = PersonNameParser.split("Tante Molly");
+        assertThat(result.title()).isEqualTo("Tante");
+        assertThat(result.firstName()).isNull();
+        assertThat(result.lastName()).isEqualTo("Molly");
+    }
+
+    @Test
+    void split_dotTitle_afterDotNorm() {
+        PersonNameParser.SplitName result = PersonNameParser.split("Dr.Fr.Zarncke");
+        assertThat(result.title()).isEqualTo("Dr.");
+        assertThat(result.firstName()).isEqualTo("Fr.");
+        assertThat(result.lastName()).isEqualTo("Zarncke");
+    }
+
+    @Test
+    void split_dotTitle_noSpace_vonLastName() {
+        PersonNameParser.SplitName result = PersonNameParser.split("Dr.von Gelden");
+        assertThat(result.title()).isEqualTo("Dr.");
+        assertThat(result.firstName()).isNull();
+        assertThat(result.lastName()).isEqualTo("von Gelden");
+    }
+
+    // --- regression: non-prefixes not stripped ---
+
+    @Test
+    void split_walter_noTitleStrip() {
+        PersonNameParser.SplitName result = PersonNameParser.split("Walter de Gruyter");
+        assertThat(result.title()).isNull();
+        assertThat(result.firstName()).isEqualTo("Walter");
+        assertThat(result.lastName()).isEqualTo("de Gruyter");
+    }
+
+    @Test
+    void split_conrad_vonGeldern_noTitleStrip() {
+        PersonNameParser.SplitName result = PersonNameParser.split("Conrad von Geldern");
+        assertThat(result.title()).isNull();
+        assertThat(result.firstName()).isEqualTo("Conrad");
+        assertThat(result.lastName()).isEqualTo("von Geldern");
+    }
+
     // --- stripMaidenName — maiden name extraction ---
 
     @Test