Support intersecting union types (concat an object with alternatives)

### Runtime

node.js

### Runtime version

22

### Module version

17.13.3

### Used with

@nahkies/openapi-code-generator

### Any other relevant information

_No response_

### What problem are you trying to solve?

Related: https://github.com/mnahkies/openapi-code-generator/issues/282

In openapi 3 definitions you can intersect schemas with unioned schemas, essentially forming something like this in typescript terms:
```typescript
(A | B) & C
```

At the moment the generator attempts to define this as something like:
```typescript
const x = joi
.alternatives()
.try(
joi
.object()
.keys({foo: joi.string().required()})
.options({stripUnknown: true})
.required(),
joi
.object()
.keys({bar: joi.string().required()})
.options({stripUnknown: true})
.required(),
)
.required()
.concat(
joi
.object()
.keys({id: joi.string().required()})
.options({stripUnknown: true})
.required(),
)
.required()
```

However this results in a runtime error like:
```
[Error: Cannot merge type alternatives with another type: object]
```
([unit test here](https://github.com/mnahkies/openapi-code-generator/pull/283/files#diff-2f29bdaaa698963024b3236513ef655df323570dd1fcc0f1476c915b8e5c69ccR1188-R1248))

### Do you have a new or modified API suggestion to solve the problem?

I'll skip that test for now, and leave it as a known issue, but it would be great if it would be possible to `concat` into `alternatives`.

**Alternatives**
I suspect I could probably come up with a way to detect definitions of this nature, and basically re-write / invert them such that it was a union of intersections, instead of an intersected union. Eg:
```typescript
(A & C) | (A & C)
```
But I think this would probably be quite complicated to do correctly supporting arbitrary input.