Create front page for Register early career teachers for schools

[TobyRet]

Ticket

429

Changes

• create new home page (markdown) with sign in links for schools and appropriate bodies. Note that DfE Signin is not wired up yet so temporary auth (personas) is used instead

Videos

Sign in as school

https://github.com/user-attachments/assets/231c34b7-854f-4678-b00b-c9ca603f217c

Sign in as appropriate body

https://github.com/user-attachments/assets/16d1fa71-dde2-4311-9abc-8247c1f3137a

[github-actions[bot]]

Review app deployed to https://cpd-ec2-review-710-web.test.teacherservices.cloud