orm: fix inserting sequential values (id=0), in tables with an i64 primary field (#18791)

vlib/orm/orm.v

@@ -209,11 +209,18 @@ pub fn orm_stmt_gen(sql_dialect SQLDialect, table string, q string, kind StmtKin
 				if data.data.len > 0 {
 					// Allow the database to insert an automatically generated primary key
 					// under the hood if it is not passed by the user.
-					if is_primary_column && data.data[i].type_idx() in orm.nums {
-						if (data.data[i] as int) == 0 {
+					tidx := data.data[i].type_idx()
+					if is_primary_column && (tidx in orm.nums || tidx in orm.num64) {
+						x := data.data[i]
+						match x {
+							i8, i16, int, i64, u8, u16, u32, u64 {
+								if i64(x) == 0 {
 									continue
 								}
 							}
+							else {}
+						}
+					}
 
 					match data.data[i].type_name() {
 						'string' {

vlib/orm/orm_insert_test.v

@@ -287,3 +287,29 @@ fn test_orm_insert_with_multiple_child_elements() {
 	assert parent.notes[1].text == 'Second note'
 	assert parent.notes[2].text == 'Third note'
 }
+
+[table: 'customers']
+struct Customer {
+	id   i64    [primary; sql: serial]
+	name string
+}
+
+fn test_i64_primary_field_works_with_insertions_of_id_0() {
+	db := sqlite.connect(':memory:')!
+	sql db {
+		create table Customer
+	}!
+	for i in ['Bob', 'Charlie'] {
+		new_customer := Customer{
+			name: i
+		}
+		sql db {
+			insert new_customer into Customer
+		}!
+	}
+	users := sql db {
+		select from Customer
+	}!
+	assert users.len == 2
+	// println("${users}")
+}