Plugin migration

[Hillshum]

This fulfills #4873 so see that for a more detailed breakdown of some pros and cons.

This PR is not intented to be merged but rather will be broken up into several smaller ones.

The list of smaller ones will likely map to this list, but may not be exact.

• Add boilerplate for supporting a Python project (packaging metadata, gitignore rules, etc)
• Change the angular config to build into a folder that the OctoPrint plugin can work with
• Read octoprint credentials from local storage or cookies
• Migrate settings to the plugin
• Remove dependencies on the Electron IPC2. Removal of electron dependencies
• Tooling to configure the system to autostart to OctoDash
• Setup wizard and migration scripts
• Settings UI
• Support for custom styles
• Support for l10n settings
• Read fan speed
• Add OctoDash restart settings in menu
• Other logic borrowed from the companion plugin
• Screen sleep