chore(coder plugin): make template names optional

[Parkreiner]

Closes #59

Changes made

• Updated CoderWorkspacesConfig by adding an isReadingEntityData value
• Added two new general-purpose components
  • InlineCodeSnippet
  • Disclosure
• Turned EntityDataReminder into ReminderAccordion (uses Disclosure as its main building block)
  • This will let us keep adding more reminder information over time as different accordion entries
  • Thought there were too many edge cases around trying to reflect the lack of a template name in the main workspaces list itself, so I pulled it out, and combined it with our existing reminder for entities
  • Similarly, I felt like adding support for 100% bespoke messages for reminders like this was too much complexity for a niche feature that might not get used. Admins can choose which reminders they want to always be turned off
  • This is also now part of the exported components for the plugin
• The main piece: made template names optional, and accounted for everything that entails
  • CoderAppConfig now exposes defaultTemplateName and defaultMode (both optional)
  • CoderWorkspacesConfig's creationUrl property is now potentially undefined
  • Updated the workspace creation links to be disabled when there is no URL
  • Updated UI to hide the call-to-action button for making workspaces when there is no usable URL
  • Added a new accordion entry that displays when there is no usable workspace creation URL
• Added/updated test cases where relevant

Edit: Squeezed in one other change at the last minute, because it seemed like a good idea. Updated CoderWorkspacesCard and CoderWorkspacesCard.Root so that they don't blow up when the value of readEntityData changes between re-renders. We're still dealing with the same technical issues as before, but instead of throwing an error, they will unmount and remount with the new prop

Notes

• Just because this PR is so chunky, I'm going to split the doc updates off into a separate PR