Launching Crystal from CLI with --readonly but with no project path should behave differently

[davidfstr]

Repro Steps:

• Run Crystal from CLI with --readonly but without specifying a project path:
  • python3 src/main.py --readonly

Expected Results:

• The Open/Create Project Dialog does appear, with the "Open as read only" checkbox pre-checked

Actual Results:

• The Open/Create Project Dialog does appear, with the "Open as read only" checkbox NOT pre-checked
• Either:
  • Continuing to either open a project will forcefully open the project as read-only, regardless of whether the "Open as read only" checkbox is checked or not.
  • Continuing to create a project will crash with a ProjectReadOnlyError on the command-line