feat(search): enhance filter value handling

- Added `checkFilterValue` function to validate and update filter values
  in `SearchStoreLive`.
- Updated `FilterItem` to handle undefined `value` gracefully by providing
  a default empty array.

These changes improve robustness in filter value processing.

frontend/app/mstore/searchStoreLive.ts

@@ -220,6 +220,7 @@ class SearchStoreLive {
   updateFilter = (index: number, search: Partial<IFilter>) => {
     const newFilters = this.instance.filters.map((_filter: any, i: any) => {
       if (i === index) {
+        search.value = checkFilterValue(search.value);
         return search;
       }
       return _filter;

frontend/app/mstore/types/filterItem.ts

@@ -157,7 +157,7 @@ export default class FilterItem {
     const json = {
       type: isMetadata ? FilterKey.METADATA : this.key,
       isEvent: Boolean(this.isEvent),
-      value: this.value.map((i: any) => (i ? i.toString() : '')),
+      value: this.value?.map((i: any) => (i ? i.toString() : '')) || [],
       operator: this.operator,
       source: isMetadata ? this.key.replace(/^_/, '') : this.source,
       sourceOperator: this.sourceOperator,