feat: infer leading period-abbreviations as titles in lastname-comma path (#109)

Complete the leading-title wiring across all three parse_full_name()
paths. Update test_brute_force test16-18, which documented the old
behavior for "Doe, John. A. Kenneth..." (unrecognized "John." parsed
as first name); it's now correctly recognized as a leading title, same
as the no-comma and suffix-comma paths.

Author: derek73

nameparser/parser.py

@@ -1033,7 +1033,7 @@ def parse_full_name(self) -> None:
 
                     if not self.first \
                             and (nxt or len(post_comma_pieces) == 1) \
-                            and self.is_title(piece):
+                            and self.is_leading_title(piece):
                         self.title_list.append(piece)
                         continue
                     if not self.first:

tests/test_brute_force.py

@@ -100,23 +100,31 @@ def test15(self) -> None:
         self.m(hn.suffix, "III", hn)
 
     def test16(self) -> None:
+        # "John." is an unrecognized period-abbreviation in the leading
+        # title position of the lastname-comma format, so is_leading_title()
+        # now treats it as a title rather than a first name (see #109).
         hn = HumanName("Doe, John. A. Kenneth")
-        self.m(hn.first, "John.", hn)
+        self.m(hn.title, "John.", hn)
+        self.m(hn.first, "A.", hn)
         self.m(hn.last, "Doe", hn)
-        self.m(hn.middle, "A. Kenneth", hn)
+        self.m(hn.middle, "Kenneth", hn)
 
     def test17(self) -> None:
+        # Same period-abbreviation-as-title behavior as test16 (see #109).
         hn = HumanName("Doe, John. A. Kenneth, Jr.")
-        self.m(hn.first, "John.", hn)
+        self.m(hn.title, "John.", hn)
+        self.m(hn.first, "A.", hn)
         self.m(hn.last, "Doe", hn)
-        self.m(hn.middle, "A. Kenneth", hn)
+        self.m(hn.middle, "Kenneth", hn)
         self.m(hn.suffix, "Jr.", hn)
 
     def test18(self) -> None:
+        # Same period-abbreviation-as-title behavior as test16 (see #109).
         hn = HumanName("Doe, John. A. Kenneth III")
-        self.m(hn.first, "John.", hn)
+        self.m(hn.title, "John.", hn)
+        self.m(hn.first, "A.", hn)
         self.m(hn.last, "Doe", hn)
-        self.m(hn.middle, "A. Kenneth", hn)
+        self.m(hn.middle, "Kenneth", hn)
         self.m(hn.suffix, "III", hn)
 
     def test19(self) -> None:

tests/test_titles.py

@@ -285,3 +285,9 @@ def test_leading_period_abbreviation_suffix_comma(self) -> None:
         self.m(hn.first, "John", hn)
         self.m(hn.last, "Smith", hn)
         self.m(hn.suffix, "Jr.", hn)
+
+    def test_leading_period_abbreviation_lastname_comma(self) -> None:
+        hn = HumanName("Smith, Major. John")
+        self.m(hn.title, "Major.", hn)
+        self.m(hn.first, "John", hn)
+        self.m(hn.last, "Smith", hn)