[AI-FSSDK] [FSSDK-12337] Add validation for experiment type field

Author: FarhanAnjum-opti

core-api/src/main/java/com/optimizely/ab/config/DatafileProjectConfig.java

@@ -195,6 +195,18 @@ public DatafileProjectConfig(String accountId,
         allExperiments.addAll(experiments);
         allExperiments.addAll(aggregateGroupExperiments(groups));
 
+        Set<String> validExperimentTypes = new HashSet<>(Arrays.asList(
+            Experiment.TYPE_AB, Experiment.TYPE_MAB, Experiment.TYPE_CMAB,
+            Experiment.TYPE_TD, Experiment.TYPE_FR
+        ));
+        for (Experiment experiment : allExperiments) {
+            if (experiment.getType() != null && !validExperimentTypes.contains(experiment.getType())) {
+                throw new ConfigParseException(
+                    String.format("Experiment \"%s\" has invalid type \"%s\". Valid types: %s.",
+                        experiment.getKey(), experiment.getType(), validExperimentTypes));
+            }
+        }
+
         // Inject "everyone else" variation into feature_rollout experiments
         allExperiments = injectFeatureRolloutVariations(allExperiments, this.featureFlags, this.rollouts);