Variadic tuples are considered non-variadic

**Describe the bug**

Version: 15.1.0

When an array contains rest syntax `ts-morph` considers the element to be a tuple. This _might_ be correct, as TypeScript would call it a variadic tuple. However, there seems to be no way to determine that the type is variadic.

**To Reproduce**

```ts
// A.ts
type A = [unknown, ...unknown[]]
```

```ts
import { Project } from 'ts-morph'

const project = new Project()
const sourceFile = project.addSourceFileAtPath(`${__dirname}/A.ts`)
const type = sourceFile.getTypeAlias('A')?.getType()

// reproduce the problem here
console.info(type?.isTuple()) // true
console.info(type?.getTupleElements().length) // 2
console.info(type?.getTupleElements()[1].isArray()) // false
console.info(type?.getTupleElements().map((x) => x.getText())) // ['unknown', 'unknown']
```

**Expected behavior**

As the type suggests that it can take any number of items, it should not be considered a straight forward tuple, but either an array or a variadic tuple.

Start with the reproduced type alias in A.ts and trace the getTypeAlias('A')?.getType() result through isTuple(), getTupleElements(), and the element isArray() checks. Compare the behavior for [unknown, ...unknown[]] with the expected variadic-tuple behavior, then verify that the type exposes a reliable distinction and that the reported reproduction produces the intended result.

Written by the indexing model from the issue text.