Misses cycles not reachable from the first file found

```console
$ echo import c > b.py
$ echo import b > c.py
$ ls
b.py c.py
$ pycycle --here
Project successfully transformed to AST, checking imports for cycles..
Cycle Found :(
b -> c: Line 1 =>> b
Finished.
$ touch a.py
$ ls
a.py b.py c.py
$ pycycle --here
Project successfully transformed to AST, checking imports for cycles..
No worries, no cycles here!
If you think some cycle was missed, please open an Issue on Github.
Finished.
```

Reproduce the issue with the shown b.py, c.py, and extra a.py files using pycycle --here. Start by tracing how the CLI chooses the first file and discovers imports; done means the b.py ↔ c.py cycle is reported whether or not a.py is present.

Written by the indexing model from the issue text.