TrafficTester: record bytes remaining

See merge request !80

Closes #40037.

Fix deprecation warning about importlib.abc.Traversable.

Closes #40037

See merge request !81

Improve CHUTNEY_PATH comments/errors

See merge request !82

* In the various `wait_done` methods, don't await potentially-cancelled
  tasks. Awaiting cancelled tasks in python is generally considered bad
  practice, and more concretely it's tricky to correctly determine
  whether a caught CancelledError while awaiting such a task is a result
  of *our* task being cancelled, in which case it should be re-raised.
  Previously we were swallowing these, which may have prevented the rest
  of cancellation from being handled properly.

  For these what we really care about are that the sockets are fully
  closed, so we just await that directly.

* In places where we want to catch and re-raise all exceptions, use
  BaseException instead of Exception. In particular CancelledError is a
  BaseException but not an Exception.

This fixes the asyncio warnings about un-retrieved task errors after the
test times out and is cancelled.

Traffic.py: improve timeout/cancellation behavior

See merge request !83

arti: Advertise dirports in arti.toml

See merge request !84

During bootstrap, gracefully handle if no descriptors are present yet.
This avoids occasional key errors when bootstrapping test networks.

Fixes #40040

LocalArtiNodeController: handle missing sqlite tables

Closes #40040

See merge request tpo/core/chutney!88

This fixes checking on recent versions of mypy, which understands
explicit version checks like this.

On recent mypy, this fixes:
```
lib/chutney/tor/controller.py:484: error: "None" object is not iterable  [misc]
```

tor controller: avoid key errors when processing descriptors

See merge request tpo/core/chutney!87

Update linters and fix newly identified type errors

See merge request tpo/core/chutney!89

arti: Advertise dirports in prop330 fashion

See merge request tpo/core/chutney!85

This is a package metadata directory which is apparently generated by
distutils. I see it when running a pip install. This is included in the
default github gitignore for python projects:

https://raw.githubusercontent.com/github/gitignore/master/Python.gitignore

Add `*.egg-info/` to gitignore

See merge request tpo/core/chutney!90

Notably, this allows us to get the hidden service key before we actually
start running the service.

This guarantees that the hostname can be retrieved after the node is
*configured*, instead of only some time after it's actually started.

Generate hidden service addresses during preConfig

See merge request tpo/core/chutney!91