feat: disable testnets in payment link form

- Add disableTestnets prop to SingleNetworkSelector component
- Apply disableTestnets to payment link form network selector

🤖 Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <[email protected]>

Author: gregfromstl

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

@@ -144,6 +144,7 @@ export function SingleNetworkSelector(props: {
   side?: "left" | "right" | "top" | "bottom";
   disableChainId?: boolean;
   align?: "center" | "start" | "end";
+  disableTestnets?: boolean;
   placeholder?: string;
   client: ThirdwebClient;
 }) {
@@ -154,8 +155,12 @@ export function SingleNetworkSelector(props: {
       return allChains;
     }
     const chainIdSet = new Set(props.chainIds);
-    return allChains.filter((chain) => chainIdSet.has(chain.chainId));
-  }, [allChains, props.chainIds]);
+    return allChains.filter(
+      (chain) =>
+        chainIdSet.has(chain.chainId) &&
+        (!props.disableTestnets || !chain.testnet),
+    );
+  }, [allChains, props.chainIds, props.disableTestnets]);
 
   const options = useMemo(() => {
     return chainsToShow.map((chain) => {

apps/dashboard/src/app/pay/components/client/PaymentLinkForm.client.tsx

@@ -205,6 +205,7 @@ export function PaymentLinkForm({ client }: { client: ThirdwebClient }) {
               chainId={chainId}
               onChange={setChainId}
               client={client}
+              disableTestnets
               className="w-full"
             />
           </div>