BUG: Setting string variable within conditional block creates undesired glue

I am running into a problem with the following pattern:

```
-> top_knot

VAR _helloTarget = "Placeholder"

=== top_knot ===
{say_hello()}.
{say_hello()}!
How are you today?
-> END

=== function say_hello() ===
{
- say_hello %2 == 1:
~ _helloTarget = "Timmy"
- else:
~ _helloTarget = "Jimmy"
}
Hello, {_helloTarget}
```

This creates the following output:

> Hello, Timmy.Hello, Jimmy!
>
> How are you today?
>
> End of story

The line break structure here is not what I want - there seems to be some mysterious glue being added to my script. After deleting the conditional block that sets _helloTarget's value...

```
=== function say_hello() ===
Hello, {_helloTarget}
```

I get the following output, with the correct line break structure but obviously the wrong text:

> Hello, Placeholder.
>
> Hello, Placeholder!
>
> How are you today?
>
> End of story

If I set _helloTarget without a conditional, I get the right line break structure, but again there is no way to get the right names:

```
=== function say_hello() ===
~ _helloTarget = "Timmy"
Hello, {_helloTarget}
```

> Hello, Timmy.
>
> Hello, Timmy!
>
> How are you today?
>
> End of story

Start by reproducing the three provided Ink snippets and comparing their line-break output, focusing on the conditional assignment inside function say_hello. The work is done when assigning _helloTarget in that conditional produces the same intended line-break structure as the unconditional version while retaining the conditional names.

Written by the indexing model from the issue text.