Summary

• require a non-empty OAuth client name during registration while preserving the legacy name fallback when client_name is absent
• normalize the controller to pass a validated client name into Passport instead of forwarding raw request input
• add focused registration tests covering the missing-name validation, legacy fallback, and client_name precedence

Validation

• vendor/bin/pest tests/Unit/Server/RegistrarTest.php --filter='requires an oauth client name|falls back to the legacy name field|prefers client_name over name'
• vendor/bin/pest tests/Unit/Server/RegistrarTest.php
• vendor/bin/pint --test src/Server/Http/Controllers/OAuthRegisterController.php tests/Unit/Server/RegistrarTest.php

Notes

• composer test:lint still fails locally because of a pre-existing src/Facades/Mcp.php Pint issue unrelated to this diff.
• composer test:unit still needs a coverage driver in this environment, so the focused Pest runs above were used for local verification.