feat: add --name-mappings param support for generator

Author: DmitrySboychakov

openapi-generator-annotations/lib/src/openapi_generator_annotations_base.dart

@@ -79,6 +79,13 @@ class Openapi {
   ///   --type-mappings
   final Map<String, String>? typeMappings;
 
+  ///  sets mappings between OpenAPI spec properties name and generated code
+  ///  var/param/model in the format of OpenAPIName=generatedName.
+  ///  For example: update=updatable,_=underscore.
+
+  ///   --name-mappings
+  final Map<String, String>? nameMappings;
+
   /// specifies mappings between a given class and the import that should
   /// be used for that class in the format of type=import,type=import. You
   /// can also have multiple occurrences of this option.
@@ -119,6 +126,7 @@ class Openapi {
     required this.generatorName,
     this.outputDirectory,
     this.typeMappings,
+    this.nameMappings,
     this.importMappings,
     this.reservedWordsMappings,
     this.inlineSchemaNameMappings,
@@ -533,8 +541,7 @@ class DioAltProperties extends AdditionalProperties {
   final String? pubspecDevDependencies;
 
   const DioAltProperties(
-      {
-      this.pubspecDependencies,
+      {this.pubspecDependencies,
       this.pubspecDevDependencies,
       this.listAnyOf,
       bool allowUnicodeIdentifiers = false,

openapi-generator/lib/src/models/generator_arguments.dart

@@ -70,6 +70,9 @@ class GeneratorArguments {
   /// Defines mappings between OpenAPI spec types and generated types.
   final Map<String, String>? typeMappings;
 
+  /// Defines mappings between OpenAPI spec var/param/model and generated code.
+  final Map<String, String>? nameMappings;
+
   /// Adds reserved words mappings.
   ///
   /// Supported by [Generator.dio] & [Generator.dioAlt] generators.
@@ -89,6 +92,7 @@ class GeneratorArguments {
         generator =
             annotations.readPropertyOrDefault('generatorName', Generator.dart),
         typeMappings = annotations.readPropertyOrNull('typeMappings'),
+        nameMappings = annotations.readPropertyOrNull('nameMappings'),
         importMappings = annotations.readPropertyOrNull('importMappings'),
         reservedWordsMappings =
             annotations.readPropertyOrNull('reservedWordsMappings'),
@@ -167,6 +171,8 @@ class GeneratorArguments {
           '--import-mappings=${importMappings!.entries.fold('', foldStringMap())}',
         if (typeMappings?.isNotEmpty ?? false)
           '--type-mappings=${typeMappings!.entries.fold('', foldStringMap())}',
+        if (nameMappings?.isNotEmpty ?? false)
+          '--name-mappings=${nameMappings!.entries.fold('', foldStringMap())}',
         if (inlineSchemaOptions != null)
           '--inline-schema-options=${inlineSchemaOptions!.toMap().entries.fold('', foldStringMap(keyModifier: convertToPropertyKey))}',
         if (additionalProperties != null)