Clean up blockly canvas page

[syuChen1]

Use better structures to represent different states from different roles.
Canvas state:
0 sandbox
1 student_day
2 mentor_day_template
3 mentor_workspace
4 mentor_sandbox
5 contentCreator_day_template
6 contentCreator_activity_template
7 contentCreator_workspace
8 contentCreator_sandbox
9 researcher_day

• Use react context to store the day object

---

• Make url param more specific (such as /student/day/:id and /content-creator/day/:id/day-template)
  OR
• Save the canvas state (such as {id: day_id, state: {role: content creator, type: day_template }} ) in the day object