MySQL enum values containing commas are corrupted by Drizzle Kit enum type splitting

## Summary

`mysqlEnum('e', ['a,b', 'c'])` can be serialized incorrectly during MySQL snapshot generation. The enum builder emits `enum('a,b','c')`, but Drizzle Kit's MySQL serializer splits the enum body on every comma, including commas inside quoted enum values.

## Steps to reproduce

1. Define a MySQL enum column with a comma inside one enum value:

```ts
mysqlEnum('e', ['a,b', 'c'])
```

2. Let the MySQL snapshot serializer normalize the generated SQL type:

```ts
enum('a,b','c')
```

3. Observe how the enum body is split.

## Expected behavior

The enum should remain two values:

```sql
enum('a,b','c')
```

The comma inside `'a,b'` should be preserved as part of the first enum value.

## Actual behavior

The serializer splits on every comma:

```ts
["'a", "b'", "'c'"]
```

In a source-level reproduction of the current serializer logic, this becomes:

```sql
enum('','','c')
```

So the original `a,b` value is not preserved.

## Evidence

- `drizzle-orm/src/mysql-core/columns/enum.ts` accepts string enum arrays through `mysqlEnum(...)`.
- The MySQL enum builder emits enum SQL by joining quoted values with commas.
- `drizzle-kit/src/serializer/mysqlSerializer.ts` reparses the enum SQL type using raw comma splitting.
- The serializer applies that parser to enum column SQL types during snapshot generation.

A minimal checked result for `['a,b', 'c']`:

- builder SQL type: `enum('a,b','c')`
- split tokens: `["'a", "b'", "'c'"]`
- serialized output: `enum('','','c')`

## Suggested fix

Parse the `enum(...)` value list as quoted SQL string literals instead of splitting on raw commas. Another option would be to avoid reparsing the SQL type string when reliable `enumValues` are already available from the column object.

A focused regression test could add a MySQL enum case with:

```ts
mysqlEnum('e', ['a,b', 'c'])
```

and assert that the generated snapshot / SQL type preserves:

```sql
enum('a,b','c')
```

## Additional context / Related coverage

A current GitHub search did not identify exact coverage for commas inside MySQL enum values. Existing nearby coverage exercises single-quote escaping for MySQL enum values. Adjacent PR `#2959` covers enum single-quote escaping, but this comma-preservation case appears separate.

---
Submitted with Codex.

Start in drizzle-kit/src/serializer/mysqlSerializer.ts and trace how MySQL enum column SQL types are parsed during snapshot generation. Review drizzle-orm/src/mysql-core/columns/enum.ts and nearby coverage for single-quote escaping, then add a regression case for mysqlEnum('e', ['a,b', 'c']). Done means the generated snapshot or SQL type preserves enum('a,b','c') with two values.

Written by the indexing model from the issue text.