support append inlay hint at end of line

when type is too long, this helps ( like union type, generic, etc)

```
class SomeVeryLonggggggggggggggggggggggggggggg:
...
def foo(): return SomeVeryLonggggggggggggggggggggggggggggg()

x = foo()
```

related in r-a https://github.com/rust-lang/rust-analyzer/issues/4318

Start by reading the related rust-analyzer issue 4318 and tracing Pyrefly's inlay-hint handling for long types. Reproduce the class and function examples, then verify that the type hint can be appended at the end of the line for long union or generic types.

Written by the indexing model from the issue text.