feat(developer): Support v2.0 projects in TIKE

Relates to #9948. Starts basic support for v2.0 projects.

For all operating modes:

- Remove blank projects / untitled projects mode
- Add Open Project Folder buttons and links
- Remove Project Save As
- Render uses in-memory XML
- Upgrade to v2.0 project file (along with checks)

For v2.0 projects:

- Remove 'Add File to Project'
- Populate Files to list all files in folder (note: consider efficiency
  here as currently files are parsed for subfile data)
- Version 2.0 project options and defaults