🛤️ Tracking: Plugin Logging

[j-lanson]

The goal is to provide some structure to plugin logging so that we can control it from the HC core. We will update plugin requirements to take a --log-level=<DEBUG/INFO/ETC> flag if they want to participate, and they will have to print out the logs in a JSON string format that we define, which includes the log level and parent/module. We then need to spawn a handler in HC core to listen for stderr, parse the JSON as it finds it, and forwards to the HC core logging subscriber. We first need to ensure this last part is possible, so it is the first subtask. Within HC core when we receive these messages, we can use tracing again to force the parent module to be plugin::<PLUGIN_NAME> so we can control whether the message gets printed with HC_LOG.
 

• Investigate how we can collect stderr handles for each plugin subprocess in HC core
• Replace log crate with tracing crate and subscriber in plugins through SDK
• SDK tracing subscriber adds plugin parent, formats logs in JSON, prints to stderr, document format requirements
• Introduce --log-level= cmdline flag for plugins and docment
• Update Command::spawn in main to handle stderr output from plugins