Add mutation to delete user

[Knerio]

close #694

[Copilot]

Pull request overview

This PR adds the ability to delete users through a new GraphQL mutation. The implementation follows the established patterns in the codebase for delete operations, including permission checks, audit logging, and proper error handling.

• Implements usersDelete GraphQL mutation with proper authorization (admin-only)
• Creates Users::DeleteService to handle the deletion business logic
• Adds comprehensive test coverage for both service and GraphQL layers

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
app/graphql/mutations/users/delete.rb	New GraphQL mutation for deleting users with validation and error handling
app/services/users/delete_service.rb	Service class implementing user deletion logic with permission checks and audit logging
app/policies/user_policy.rb	Adds :delete_user permission to admin policy
app/models/audit_event.rb	Registers :user_deleted audit event type
app/graphql/types/mutation_type.rb	Mounts the new Mutations::Users::Delete mutation
spec/services/users/delete_service_spec.rb	Service-level tests for user deletion with permission checks
spec/graphql/mutations/users/delete_spec.rb	Unit tests for GraphQL mutation naming
spec/requests/graphql/mutation/users/delete_spec.rb	Integration tests for the mutation endpoint
docs/graphql/mutation/usersdelete.md	API documentation for the new mutation

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[github-actions]

GitLab Pipeline Action

General information

Link to pipeline: https://gitlab.com/code0-tech/development/sagittarius/-/pipelines/2173850855

Status: Passed
Duration: 3 minutes

Job summaries

rspec: [ee]

Coverage report available at https://code0-tech.gitlab.io/-/development/sagittarius/-/jobs/12183907460/artifacts/tmp/coverage/index.html
Test summary available at https://gitlab.com/code0-tech/development/sagittarius/-/pipelines/2173850855/test_report
Finished in 18.84 seconds (files took 13.55 seconds to load)
1222 examples, 0 failures
Line Coverage: 91.34% (4146 / 4539)
[TEST PROF INFO] Time spent in factories: 00:10.755 (41.54% of total time)

rspec: [ce]

Coverage report available at https://code0-tech.gitlab.io/-/development/sagittarius/-/jobs/12183907459/artifacts/tmp/coverage/index.html
Test summary available at https://gitlab.com/code0-tech/development/sagittarius/-/pipelines/2173850855/test_report
Finished in 18.81 seconds (files took 11.76 seconds to load)
1175 examples, 0 failures
Line Coverage: 90.74% (3978 / 4384)
[TEST PROF INFO] Time spent in factories: 00:10.635 (41.51% of total time)

rubocop

688 files inspected, no offenses detected

[Copilot]

Pull request overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated 2 comments.

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