DBP-99: clean up backend default groups

[pan93412]

• refactor: clean up permissions
• refactor: refine default scope set and group
• chore(setup): update description
• refactor(setup): update all new-user references
• refactor(setup): update all references to 'verification'

[linear]

DBP-99 clean up backend default groups

[Copilot]

Pull Request Overview

This PR refactors the user account system by renaming "new-user" to "student" and simplifying the verification system. It removes the verification flow that allowed users to self-verify and transitions to a manual verification system by administrators.

• Renamed all "new-user" references to "student" throughout the codebase
• Removed the verification mutation and related GraphQL endpoints
• Updated scope sets to remove verification permissions and add student-specific permissions

Reviewed Changes

Copilot reviewed 19 out of 19 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
internal/useraccount/models.go	Updated constants to rename new-user to student
internal/useraccount/register_flow.go	Updated verification flow to use student group
internal/setup/setup.go	Refactored setup to create student group instead of new-user group
graph/user.graphqls	Removed verification mutation endpoint
graph/user.resolvers.go	Removed verification resolver implementation
docs/scope.md	Updated scope documentation to remove verification scope
Multiple test files	Updated tests to use student group instead of new-user group

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[Copilot]

Pull Request Overview

Copilot reviewed 19 out of 19 changed files in this pull request and generated 3 comments.

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