Update Swift accessor schema for swift-syntax 604

Model accessor modifiers as a collection in the Swift input schema and refresh the affected corpus snapshots for the swift-syntax 604 AST shape.

Author: Copilot

unified/extractor/swift_node_types.yml

@@ -273,7 +273,7 @@ named:
     endOfFileToken: _token
   accessorDecl:
     attributes*: [attribute, ifConfigDecl]
-    modifier?: declModifier
+    modifiers*: declModifier
     accessorSpecifier: _token
     parameters?: accessorParameters
     effectSpecifiers?: accessorEffectSpecifiers

unified/extractor/tests/corpus/swift/types/binding-modifier-does-not-leak-into-accessor-body.output

@@ -87,6 +87,7 @@ sourceFile
                                         declReferenceExpr
                                           baseName: identifier "y"
                                       switchKeyword: switch
+                      modifiers:
                   leftBrace: {
                   rightBrace: }
 

unified/extractor/tests/corpus/swift/types/property-with-getter-and-setter.output

@@ -75,6 +75,7 @@ sourceFile
                                                 declReferenceExpr
                                                   baseName: identifier "_v"
                                               returnKeyword: return
+                                  modifiers:
                                 accessorDecl
                                   accessorSpecifier: set
                                   attributes:
@@ -95,6 +96,7 @@ sourceFile
                                               rightOperand:
                                                 declReferenceExpr
                                                   baseName: identifier "newValue"
+                                  modifiers:
                               leftBrace: {
                               rightBrace: }
           modifiers:

unified/extractor/tests/corpus/swift/types/protocol-with-read-only-and-read-write-property-requirements.output

@@ -42,6 +42,7 @@ sourceFile
                                 accessorDecl
                                   accessorSpecifier: get
                                   attributes:
+                                  modifiers:
                               leftBrace: {
                               rightBrace: }
                 memberBlockItem
@@ -67,9 +68,11 @@ sourceFile
                                 accessorDecl
                                   accessorSpecifier: get
                                   attributes:
+                                  modifiers:
                                 accessorDecl
                                   accessorSpecifier: set
                                   attributes:
+                                  modifiers:
                               leftBrace: {
                               rightBrace: }
                 memberBlockItem
@@ -95,6 +98,7 @@ sourceFile
                                 accessorDecl
                                   accessorSpecifier: get
                                   attributes:
+                                  modifiers:
                               leftBrace: {
                               rightBrace: }
           modifiers:

unified/extractor/tests/corpus/swift/variables/property-with-willset-and-didset-observers.output

@@ -68,6 +68,7 @@ sourceFile
                                               calledExpression:
                                                 declReferenceExpr
                                                   baseName: identifier "print"
+                                  modifiers:
                                 accessorDecl
                                   accessorSpecifier: didSet
                                   attributes:
@@ -90,6 +91,7 @@ sourceFile
                                               calledExpression:
                                                 declReferenceExpr
                                                   baseName: identifier "print"
+                                  modifiers:
                               leftBrace: {
                               rightBrace: }
           modifiers: