Bad error messages

1. Fails pointing to the equality and claiming that an SMT query failed

```pulse
fn value_of (#a:Type) (r:ref a)
requires pts_to r 'v
returns v:a
ensures pts_to r 'v ** pure (v == 'v)
{
'v
}
```

2. Points to the (!i) but fails saying expected `int` got `stt int .... ` which is a bit cryptic

```pulse
fn four_fail ()
requires emp
returns i:int
ensures pure (i == 4)
{
let mut i = 1;
add i (!i);
add i (!i);
!i
}
```

No files or tests are named. Start by reproducing the `value_of` and `four_fail` Pulse snippets and inspect the diagnostics they produce; done means the reported locations and messages identify the underlying failures rather than the misleading SMT or type descriptions.

Written by the indexing model from the issue text.