preserve `Literal` through generic function calls

### Describe the Bug

```py
def f[T](t: T) -> T:
    return t

reveal_type(1)  # Literal[1]
a = 1
reveal_type(a)  # Literal[1]
reveal_type(f(a))  # int, expect Literal[1]
reveal_type(f(1))  # int, expect Literal[1]
```

### Sandbox Link

_No response_

### (Only applicable for extension issues) IDE Information

_No response_