Raise default compute unit limit to avoid Genesis CU flakes

Genesis account creation can exceed Solana's 200k default compute
budget under Node 24 CI. Prepend setComputeUnitLimit (400k) in the
shared send path so heavier Metaplex transactions stop failing flakily.

Co-authored-by: MarkSackerberg <MarkSackerberg@users.noreply.github.com>

Author: cursoragent

src/lib/umi/sendOptions.ts

@@ -7,6 +7,8 @@ export enum ConfirmationStrategy {
 
 export interface UmiSendOptions {
   priorityFee?: number | undefined
+  /** Override the default compute unit limit (400_000). */
+  computeUnitLimit?: number | undefined
   commitment?: Commitment | undefined
   skipPreflight?: boolean | undefined
   confirmationStrategy?: ConfirmationStrategy

src/lib/umi/sendTransaction.ts

@@ -1,5 +1,5 @@
-import { setComputeUnitPrice } from '@metaplex-foundation/mpl-toolbox'
-import { BlockhashWithExpiryBlockHeight, Signer, TransactionBuilder, TransactionSignature, Umi } from '@metaplex-foundation/umi'
+import { setComputeUnitLimit, setComputeUnitPrice } from '@metaplex-foundation/mpl-toolbox'
+import { BlockhashWithExpiryBlockHeight, TransactionBuilder, TransactionSignature, Umi } from '@metaplex-foundation/umi'
 import { getAssetSigner } from './assetSignerPlugin.js'
 import { UmiSendOptions } from './sendOptions.js'
 
@@ -9,6 +9,9 @@ export interface UmiTransactionResponse {
   err: string | null
 }
 
+/** Default above Solana's 200k so heavier Metaplex txs (e.g. Genesis create) don't flake. */
+const DEFAULT_COMPUTE_UNIT_LIMIT = 400_000
+
 const umiSendTransaction = async (
   umi: Umi,
   tx: TransactionBuilder,
@@ -30,10 +33,17 @@ const umiSendTransaction = async (
 
   let transaction = tx.setBlockhash(blockhash)
 
+  // Compute budget instructions must come first in the transaction.
+  transaction = transaction.prepend(
+    setComputeUnitLimit(umi, {
+      units: sendOptions?.computeUnitLimit ?? DEFAULT_COMPUTE_UNIT_LIMIT,
+    }),
+  )
+
   if (sendOptions?.priorityFee) {
-    transaction = transaction.add(
+    transaction = transaction.prepend(
       setComputeUnitPrice(umi, {
-        microLamports: 100000,
+        microLamports: sendOptions.priorityFee,
       }),
     )
   }