Fix linting errors

- Remove ineffectual assignment in cel2sql.go
- Fix unused parameter by renaming to underscore
- Replace fmt.Sprintf with string concatenation for better performance
- All golangci-lint issues resolved

Author: richardwooding

cel2sql.go

@@ -449,7 +449,6 @@ func (con *converter) visitCallFunc(expr *exprpb.Expr) error {
 			case argType.GetPrimitive() == exprpb.Type_BYTES:
 				sqlFun = "LENGTH"
 			case isListType(argType):
-				sqlFun = "ARRAY_LENGTH"
 				// For PostgreSQL, we need to specify the array dimension (1 for 1D arrays)
 				con.str.WriteString("ARRAY_LENGTH(")
 				if target != nil {
@@ -870,7 +869,7 @@ func isFieldAccessExpression(expr *exprpb.Expr) bool {
 	return false
 }
 
-func (con *converter) callTimestampFromString(target *exprpb.Expr, args []*exprpb.Expr) error {
+func (con *converter) callTimestampFromString(_ *exprpb.Expr, args []*exprpb.Expr) error {
 	if len(args) == 1 {
 		// For PostgreSQL, we need to cast the string to a timestamp
 		con.str.WriteString("CAST(")

pg/provider_testcontainer_test.go

@@ -375,7 +375,7 @@ func TestCELToSQL_ComprehensiveIntegration(t *testing.T) {
 		t.Logf("Complex date CEL: %s", celExpression)
 		t.Logf("Complex date SQL: %s", sqlCondition)
 
-		query := fmt.Sprintf("SELECT COUNT(*) FROM users WHERE %s", sqlCondition)
+		query := "SELECT COUNT(*) FROM users WHERE " + sqlCondition
 		var count int
 		err = pool.QueryRow(ctx, query).Scan(&count)
 		require.NoError(t, err)
@@ -399,7 +399,7 @@ func TestCELToSQL_ComprehensiveIntegration(t *testing.T) {
 		t.Logf("Complex array CEL: %s", celExpression)
 		t.Logf("Complex array SQL: %s", sqlCondition)
 
-		query := fmt.Sprintf("SELECT COUNT(*) FROM products WHERE %s", sqlCondition)
+		query := "SELECT COUNT(*) FROM products WHERE " + sqlCondition
 		var count int
 		err = pool.QueryRow(ctx, query).Scan(&count)
 		require.NoError(t, err)