feat: [WD-13702] Add publish instance

[Kxiru]

Done

• Created PublishInstanceForm Component
• Created PublishInstanceBtn Component
• Added PIBtn to Instance detail page
• Added API call to 1.0/images/ to create a new Image.

QA

1. Run the LXD-UI:
   • On the demo server via the link posted by @webteam-app below. This is only available for PRs created by collaborators of the repo. Ask @mas-who or @edlerd for access.
   • With a local copy of this branch, build and run as described in the docs.
2. Perform the following QA steps:
   • View an Instance detail page and publish an instance using the button.
   • Verify the instance has created an image by navigating to the image page.

Screenshots