fix(solana): fix simulator side effect bug

If we create a simulator with an executor, on construction of that simulator, the sendAndConfirm function is overwritten with a no-op version.

```
executor := mcmsSolana.NewExecutor(s.SolanaClient, auth, encoder)
simulator := mcmsSolana.NewSimulator(executor)
simulator.SimulateSetRoot(....)

executor.SetRoot(....) ????? This will not perform any transaction
```

This commit ensure a copy of executor is modified.

Side note: i combined the e2e simulator test with the e2e executor test so we can simulate and perform the actual operation, not to mention we saved a bunch of setup.

JIRA: https://smartcontract-it.atlassian.net/browse/DPA-1417

.changeset/real-kangaroos-sit.md

@@ -0,0 +1,5 @@
+---
+"@smartcontractkit/mcms": patch
+---
+
+fix(solana): fix simulator side effect bug

e2e/tests/solana/execute.go

@@ -6,6 +6,7 @@ package solanae2e
 import (
 	"context"
 	"math/big"
+	"slices"
 	"time"
 
 	"github.com/ethereum/go-ethereum/common"
@@ -88,7 +89,8 @@ func (s *SolanaTestSuite) Test_Solana_Execute() {
 	encoders, err := proposal.GetEncoders()
 	s.Require().NoError(err)
 	encoder := encoders[s.ChainSelector].(*mcmsSolana.Encoder)
-	executors := map[types.ChainSelector]sdk.Executor{s.ChainSelector: mcmsSolana.NewExecutor(encoder, s.SolanaClient, auth)}
+	executor := mcmsSolana.NewExecutor(encoder, s.SolanaClient, auth)
+	executors := map[types.ChainSelector]sdk.Executor{s.ChainSelector: executor}
 	inspectors := map[types.ChainSelector]sdk.Inspector{s.ChainSelector: mcmsSolana.NewInspector(s.SolanaClient)}
 
 	// sign proposal
@@ -103,6 +105,34 @@ func (s *SolanaTestSuite) Test_Solana_Execute() {
 	_, err = configurer.SetConfig(ctx, mcmID, &mcmConfig, true)
 	s.Require().NoError(err)
 
+	// simulate SetRoot
+	metadata := proposal.ChainMetadata[s.ChainSelector]
+	metadataHash, err := encoder.HashMetadata(metadata)
+	s.Require().NoError(err)
+
+	tree, err := proposal.MerkleTree()
+	s.Require().NoError(err)
+
+	proof, err := tree.GetProof(metadataHash)
+	s.Require().NoError(err)
+
+	hash, err := proposal.SigningHash()
+	s.Require().NoError(err)
+
+	// Sort signatures by recovered address
+	sortedSignatures := slices.Clone(proposal.Signatures) // Clone so we don't modify the original
+	slices.SortFunc(sortedSignatures, func(a, b types.Signature) int {
+		recoveredSignerA, _ := a.Recover(hash)
+		recoveredSignerB, _ := b.Recover(hash)
+
+		return recoveredSignerA.Cmp(recoveredSignerB)
+	})
+
+	simulator := mcmsSolana.NewSimulator(executor)
+	err = simulator.SimulateSetRoot(ctx, "", metadata,
+		proof, [32]byte(tree.Root.Bytes()), proposal.ValidUntil, sortedSignatures)
+	s.Require().NoError(err)
+
 	// call SetRoot
 	executable, err := mcms.NewExecutable(proposal, executors)
 	s.Require().NoError(err)

sdk/solana/executor.go

@@ -41,9 +41,9 @@ func NewExecutor(encoder *Encoder, client *rpc.Client, auth solana.PrivateKey) *
 	}
 }
 
-func (e *Executor) withSendAndConfirmFn(fn SendAndConfirmFn) *Executor {
+func (e Executor) withSendAndConfirmFn(fn SendAndConfirmFn) *Executor {
 	e.sendAndConfirm = fn
-	return e
+	return &e
 }
 
 // ExecuteOperation executes an operation on the MCMS program on the Solana chain

sdk/solana/simulator_test.go

@@ -30,16 +30,28 @@ func TestSimulator_SimulateSetRoot(t *testing.T) {
 	}
 
 	tests := []struct {
-		name          string
-		setupMocks    func(t *testing.T, client *mocks.JSONRPCClient)
-		expectedError string
+		name           string
+		setupMocks     func(t *testing.T, client *mocks.JSONRPCClient)
+		executeSetRoot bool
+		expectedError  string
 	}{
 		{
 			name: "success",
 			setupMocks: func(t *testing.T, client *mocks.JSONRPCClient) {
 				t.Helper()
 				mockSolanaSimulateTransaction(t, client, 50, nil, nil)
+
+				// for real execution
+				mockSolanaTransaction(t, client, 50, 60,
+					"AxzwxQ2DLR4zEFxEPGaafR4z3MY4CP1CAdSs1ZZhArtgS3G4F9oYSy3Nx1HyA1Macb4bYEi4jU6F1CL4SRrZz1v", nil, nil)
+				mockSolanaTransaction(t, client, 51, 61,
+					"3DqeyZzb7PJmQ31M1qdXfP7iACr5AiEXcKeLUNmVvDoYM23JJK5ZvermxsDy8eiQKzpagc69MKRtrpzK7tRcLGgr", nil, nil)
+				mockSolanaTransaction(t, client, 52, 62,
+					"GHR9z23oUJnS2aV5HZ9zEpUpEe4qoBLFMzuBjNA3xJcQuc6JjDmuUq2VVmxqwPeFzfs8V7nfjqc1wRviEb82bRu", nil, nil)
+				mockSolanaTransaction(t, client, 53, 63,
+					"oaV9FKKPDVneUANQ9hJqEuhgwfUgbxucUC4TmzpgGJhuSxBueapWc9HJ4cJQMqT2PPQX6rhTbKnXkebsaravnLo", nil, nil)
 			},
+			executeSetRoot: true,
 		},
 		{
 			name: "failure: GetLastBlockhash error",
@@ -75,6 +87,12 @@ func TestSimulator_SimulateSetRoot(t *testing.T) {
 			} else {
 				require.NoError(t, err)
 			}
+
+			if tt.executeSetRoot {
+				result, err := executor.SetRoot(ctx, metadata, proof, root, validUntil, signatures)
+				require.NoError(t, err)
+				require.NotNil(t, result)
+			}
 		})
 	}
 }

sdk/solana/utils_test.go

@@ -176,7 +176,7 @@ func mockSolanaSimulateTransaction(
 		}}
 
 		return mockBlockHashRPCError
-	})
+	}).Once()
 	if mockBlockHashRPCError != nil {
 		return
 	}
@@ -195,7 +195,7 @@ func mockSolanaSimulateTransaction(
 		}
 
 		return nil
-	})
+	}).Once()
 }
 
 var sendTransactionParams = func(t *testing.T) any {