Feature/1175 add minos support

[filippo-20tab]

Summary

Modernizes the Next.js bootstrapper to produce Minos-aligned service repos. Deployments now run via the Minos service module image and OpenTofu GitLab Components (opentofu/apply@3.11.0); the legacy stacks model is replaced with an env_to_cluster mapping (default {development: dev, staging: dev, production: main}).

Reference output: gs1-procedo/frontend, gs1-one/backoffice. Part of TG-1175 (sister PRs on django-continuous-delivery and talos).

Highlights

• stacks + environments_distribution + deployment_type ⟶ env_to_cluster: dict[str, str]
• Emits minos/ skeleton (common.tfvars + {development,staging,production}/{this.tfvars,shared-config.yaml}); no postgres_* (frontend-only)
• New service-style .gitlab-ci.yml (stages: Test / Pact-publish / Pact-check / Build / Report / Deploy / Pact-tag / Sentry); per-env buildah builds for NEXT_PUBLIC_* bake-time
• Multi-stage remote.Dockerfile on node:24.14.0-alpine, yarn-corepack, --mount=type=secret for SENTRY_AUTH_TOKEN
• Vault helper renamed register_vault_environment_secret → register_vault_service_secret (path ${PROJECT_SLUG}/envs/{env}/{service_slug}/{key})
• ci_pact.sh/ci_sentry.sh reduced to source-only Vault loaders

Breaking changes

• CLI: --deployment-type, --environments-distribution removed
• cookiecutter.json: deployment_type, stacks, environment_distribution removed; host: "" added per env
• Generated repos: terraform/ and scripts/deploy/ no longer emitted

Testing

6 new/updated tests in test_collector.py pass (test_env_to_cluster_*, test_get_runner, test_collect, test_launch_runner). The 9 pre-existing errors in test_helpers.py (modern-click mock issues on validate_or_prompt_secret) are present on main too — out of scope.

Merge order

Land before the corresponding talos PR — talos clones the sub-bootstrappers via FRONTEND_TEMPLATE_URLS, so this branch must be on the remote for the end-to-end test.