[AI-FSSDK] [FSSDK-12337] Add EXPERIMENT_TYPES constant with enum validation

- Define EXPERIMENT_TYPES constant with valid experiment type values
  (ab, mab, cmab, td, fr) in Constants module
- Use enum constraint in JSON schema to validate the type field
- Reference constant in injection check instead of raw string literal
- Add flag_variation_map assertion to variation maps test

Author: FarhanAnjum-opti

lib/optimizely/config/datafile_project_config.rb

@@ -212,7 +212,7 @@ def initialize(datafile, logger, error_handler)
 
         feature_flag['experimentIds'].each do |exp_id|
           experiment = @experiment_id_map[exp_id]
-          next unless experiment && experiment['type'] == 'feature_rollout'
+          next unless experiment && experiment['type'] == Helpers::Constants::EXPERIMENT_TYPES['fr']
 
           experiment['variations'].push(everyone_else_variation)
           experiment['trafficAllocation'].push(

lib/optimizely/helpers/constants.rb

@@ -18,6 +18,14 @@
 module Optimizely
   module Helpers
     module Constants
+      EXPERIMENT_TYPES = {
+        'ab' => 'a/b',
+        'mab' => 'mab',
+        'cmab' => 'cmab',
+        'td' => 'targeted_delivery',
+        'fr' => 'feature_rollout'
+      }.freeze
+
       JSON_SCHEMA_V2 = {
         'type' => 'object',
         'properties' => {
@@ -206,7 +214,8 @@ module Constants
                   'type' => 'object'
                 },
                 'type' => {
-                  'type' => 'string'
+                  'type' => %w[string null],
+                  'enum' => EXPERIMENT_TYPES.values + [nil]
                 },
                 'holdouts' => {
                   'type' => 'array'

spec/config/datafile_project_config_spec.rb

@@ -2008,6 +2008,11 @@ def build_datafile(experiments: [], rollouts: [], feature_flags: [])
       expect(config.variation_id_map['feature_rollout_exp']).to have_key('everyone_else_var')
       expect(config.variation_id_map_by_experiment_id['exp_fr']).to have_key('everyone_else_var')
       expect(config.variation_key_map_by_experiment_id['exp_fr']).to have_key('everyone_else_var')
+
+      # flag_variation_map should also include the injected variation
+      flag_variations = config.flag_variation_map['test_flag']
+      injected_ids = flag_variations.map { |v| v['id'] }
+      expect(injected_ids).to include('everyone_else_var')
     end
 
     it 'should not modify non-feature_rollout experiments' do