fix: add strategy bug when strategySplittedButton flag is on (#4071)

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Fixes 2 bugs after the recent strategy improvements v2 changes:
- When creating a strategy the `groupId` param of the Gradual Rollout
strategy now populates the groupId (when using default strategy, the
groupId will only be overwritten when it is an empty string ) with the
feature name (as it was before)

- When editing/setting a default strategy for an environment the
`groupId` param should be an empty string, but editable.

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---------

Signed-off-by: andreas-unleash <andreas@getunleash.ai>

frontend/src/component/feature/FeatureStrategy/FeatureStrategyCreate/FeatureStrategyCreate.tsx

@@ -33,7 +33,7 @@ import { usePlausibleTracker } from 'hooks/usePlausibleTracker';
 import useQueryParams from 'hooks/useQueryParams';
 import useProject from 'hooks/api/getters/useProject/useProject';
 import { useSegments } from 'hooks/api/getters/useSegments/useSegments';
-import { DEFAULT_STRATEGY } from '../../../project/Project/ProjectSettings/ProjectDefaultStrategySettings/ProjectEnvironment/ProjectEnvironmentDefaultStrategy/EditDefaultStrategy';
+import { DEFAULT_STRATEGY } from 'component/project/Project/ProjectSettings/ProjectDefaultStrategySettings/ProjectEnvironment/ProjectEnvironmentDefaultStrategy/EditDefaultStrategy';
 
 export const FeatureStrategyCreate = () => {
     const projectId = useRequiredPathParam('projectId');
@@ -101,11 +101,19 @@ export const FeatureStrategyCreate = () => {
 
     useEffect(() => {
         if (shouldUseDefaultStrategy) {
-            setStrategy((defaultStrategy as any) || DEFAULT_STRATEGY);
+            const strategyTemplate = defaultStrategy || DEFAULT_STRATEGY;
+            if (strategyTemplate.parameters?.groupId === '' && featureId) {
+                strategyTemplate.parameters.groupId = featureId;
+            }
+            setStrategy(strategyTemplate as any);
         } else if (strategyDefinition) {
             setStrategy(createFeatureStrategy(featureId, strategyDefinition));
         }
-    }, [featureId, strategyDefinition, shouldUseDefaultStrategy]);
+    }, [
+        featureId,
+        JSON.stringify(strategyDefinition),
+        shouldUseDefaultStrategy,
+    ]);
 
     const onAddStrategy = async (payload: IFeatureStrategyPayload) => {
         await addStrategyToFeature(

frontend/src/component/feature/StrategyTypes/FlexibleStrategy/FlexibleStrategy.tsx

@@ -14,8 +14,9 @@ import {
 import { StickinessSelect } from './StickinessSelect/StickinessSelect';
 import { useDefaultProjectSettings } from 'hooks/useDefaultProjectSettings';
 import Loader from '../../../common/Loader/Loader';
-import { useMemo } from 'react';
+import { useEffect, useMemo } from 'react';
 import { useRequiredPathParam } from 'hooks/useRequiredPathParam';
+import { useLocation } from 'react-router';
 
 interface IFlexibleStrategyProps {
     parameters: IFeatureStrategyParameters;
@@ -31,7 +32,9 @@ const FlexibleStrategy = ({
 }: IFlexibleStrategyProps) => {
     const projectId = useRequiredPathParam('projectId');
     const { defaultStickiness, loading } = useDefaultProjectSettings(projectId);
+    const { pathname } = useLocation();
 
+    const isDefaultStrategyEdit = pathname.includes('default-strategy');
     const onUpdate = (field: string) => (newValue: string) => {
         updateParameter(field, newValue);
     };
@@ -57,6 +60,12 @@ const FlexibleStrategy = ({
         onUpdate('stickiness')(stickiness);
     }
 
+    useEffect(() => {
+        if (isDefaultStrategyEdit) {
+            onUpdate('groupId')('');
+        }
+    }, [isDefaultStrategyEdit]);
+
     if (loading) {
         return <Loader />;
     }