Clarify portal GitLab trigger scope

[yoshifuminakamura]

Summary

• show the configured GitLab project next to each Portal trigger target
• label exp as Profile Exp and warn that it is Portal-side matching metadata, not a GitLab CI filter
• record the selected GitLab project in dry-run and submit execution request payloads

Validation

• /home/nakamura/fugakunext/venv/bin/python -m py_compile result_server/routes/admin.py result_server/utils/gitlab_pipeline.py
• /home/nakamura/fugakunext/venv/bin/python -m pytest result_server/tests/test_execution_profiles.py result_server/tests/test_app_dev_security.py result_server/tests/test_api_routes.py result_server/tests/test_preflight.py