Create a dedicated page on debugging the code

[nazarewk]

Is your feature request related to a problem? Please describe

As somebody with years of experience with IaC tooling (mostly Terraform, occasional Ansible) I had trouble finding any resources on how to interact with and debug the pyinfra code.

After failing to use PyCharm debugger and searching through docs I came up with this frankenstein (which nobody should use) to print out databases in MySQL:

# DO NOT USE
databases = host.get_fact(MysqlDatabases, **mysql_args)
server.shell(commands=[f"echo 'Hello World!' {databases}"])

what I later learned it could look like:

from pyinfra import logger
databases = host.get_fact(MysqlDatabases, **mysql_args)
logger.info(json.dumps(databases, indent=2, sort_keys=True))

Describe the solution you'd like

It would be great to have a debugging instructions page dedicated to new users. Some stuff it could include, which I learned after brief talk on Matrix chat/through issues:

• make it obvious that re-running operations it currently the only sensible way to learn/reason about and debug the code.
• point out that from pyinfra import logger can aid this model with "print driven debugging".
• note that pyinfra doesn't really work with Jetbrains/PyCharm debugger, remove the compatibility docs saying otherwise.
• make it obvious step by step debugging is not (currently?) available due to heavily asynchronous execution model
• I've seen it somewhere that pyinfra execution model doesn't allow retrieving outputs from operations (only facts).