[FEATURE]: Add text(..., { mode: "timestamp" }) support to SQLite

### Describe what you want

Currently, SQLite allows default values for a `text` column to be set as `CURRENT_TIMESTAMP`. Drizzle however only automatically casts `integer(..., { mode: 'timestamp' }` (and `_ms`) to `Date` objects, making those two features incompatible.

We should allow `text` to also be a `timestamp` so it can be used in conjunction with the default value:

```js
export const log = sqliteTable("log", {
id: integer("id").primaryKey(),
// ...
created:
text("created", { mode: "timestamp" })
.default(sql`(CURRENT_TIMESTAMP)`),
});
```

Expecting `created` to be of type `Date` when selecting.

### Why?

Currently it isn't possible to achieve the "default to current timestamp" when columns are of type integer, only text.

Start at the SQLite text(...) and integer(..., { mode: "timestamp" }) column implementations, then locate their existing type or mapping tests. Trace how the mode affects selected values and the default sql`(CURRENT_TIMESTAMP)` expression. Done means text("created", { mode: "timestamp" }) accepts the configuration and selecting the column returns a Date, with coverage for the example case.

Written by the indexing model from the issue text.