unified: Get rid of some "." bleed

Adds a new type `nested_type_identifier`, which contains the
choice-branch that previously allowed those tokens to bleed through into
the closest parent field.

unified/extractor/tree-sitter-swift/grammar.js

@@ -1592,13 +1592,11 @@ module.exports = grammar({
         choice($._equal_sign, $._eq_eq),
         field("must_equal", $._type)
       ),
-    _constrained_type: ($) =>
-      choice(
-        $.identifier,
-        seq(
-          $.unannotated_type,
-          optional(seq(".", sep1($.simple_identifier, ".")))
-        )
+    _constrained_type: ($) => choice($.identifier, $.nested_type_identifier),
+    nested_type_identifier: ($) =>
+      seq(
+        $.unannotated_type,
+        optional(seq(".", sep1($.simple_identifier, ".")))
       ),
     _class_member_separator: ($) => choice($._semi, $.multiline_comment),
     _class_member_declarations: ($) =>

unified/extractor/tree-sitter-swift/node-types.yml

@@ -203,7 +203,7 @@ named:
     name*: unannotated_type
   equality_constraint:
     $children*: attribute
-    constrained_type+: [".", identifier, simple_identifier, unannotated_type]
+    constrained_type: [identifier, nested_type_identifier]
     must_equal+: [type_modifiers, unannotated_type]
     name: unannotated_type
   equality_expression:
@@ -259,7 +259,7 @@ named:
     rhs: expression
   inheritance_constraint:
     $children*: attribute
-    constrained_type+: [".", identifier, simple_identifier, unannotated_type]
+    constrained_type: [identifier, nested_type_identifier]
     inherits_from+: [implicitly_unwrapped_type, type_modifiers, unannotated_type]
     name?: unannotated_type
   inheritance_modifier:
@@ -330,6 +330,8 @@ named:
     target+: ["(", ")", array_type, dictionary_type, existential_type, expression, opaque_type, user_type]
   navigation_suffix:
     suffix: [integer_literal, simple_identifier]
+  nested_type_identifier:
+    $children+: [simple_identifier, unannotated_type]
   nil_coalescing_expression:
     if_nil: expression
     value: expression