[NEB-173]: Hide testnets in nebula chain selector (#6746)

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## PR-Codex overview
This PR introduces the ability to hide test networks in the `MultiNetworkSelector` component and updates its props accordingly.

### Detailed summary
- Added `hideTestnets` prop to `MultiNetworkSelector` in `NetworkSelectors.tsx`.
- Implemented filtering of `sortedChains` to exclude test networks if `hideTestnets` is true.
- Updated dependency array in `useEffect` to include `props.hideTestnets`.

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Author: MananTank

apps/dashboard/src/@/components/blocks/NetworkSelectors.tsx

@@ -19,6 +19,7 @@ export function MultiNetworkSelector(props: {
   disableChainId?: boolean;
   className?: string;
   priorityChains?: number[];
+  hideTestnets?: boolean;
 }) {
   const { allChains, idToChain } = useAllChainsData();
 
@@ -44,13 +45,17 @@ export function MultiNetworkSelector(props: {
       sortedChains = [...priorityChains, ...otherChains];
     }
 
+    if (props.hideTestnets) {
+      sortedChains = sortedChains.filter((chain) => !chain.testnet);
+    }
+
     return sortedChains.map((chain) => {
       return {
         label: cleanChainName(chain.name),
         value: String(chain.chainId),
       };
     });
-  }, [allChains, props.priorityChains, idToChain]);
+  }, [allChains, props.priorityChains, idToChain, props.hideTestnets]);
 
   const searchFn = useCallback(
     (option: Option, searchValue: string) => {

apps/dashboard/src/app/nebula-app/(app)/components/ContextFilters.tsx

@@ -189,6 +189,7 @@ export function ContextFiltersForm(props: {
                 <FormLabel>Chain IDs</FormLabel>
                 <FormControl>
                   <MultiNetworkSelector
+                    hideTestnets
                     disableChainId
                     className="bg-background"
                     selectedChainIds={form