[SDK] feat: Add fixed gas limit for Saga Mainnet (#6500)

Author: joaquim-verges

packages/thirdweb/src/transaction/actions/estimate-gas.ts

@@ -73,6 +73,10 @@ export async function estimateGas(
     // biome-ignore lint/style/noNonNullAssertion: the `has` above ensures that this will always be set
     return cache.get(txWithFrom)!;
   }
+  // Saga Mainnet has a fixed gas limit for all transactions
+  if (options.transaction.chain.id === 5464) {
+    return 20000000n;
+  }
   const { account } = options;
   const promise = (async () => {
     const predefinedGas = await resolvePromisedValue(options.transaction.gas);