feat: upgrade app template server from vet reference
- integer-id persistence: memory (default, zero-dep) + mongo_int repos
selected by REPO_BACKEND via create_repo factory
- interfaces/_common.py: shared svc/dump/paginate/expand_ref/read_or_404
helpers; item/job routes rebuilt on them (paginated {total,items} lists,
PUT replace, 204 deletes, int path ids)
- interfaces/system: /health liveness probe (public)
- openapi.yaml rewritten to 3.1.0 with x- extensions on Item/Job
(x-resource, x-primary-key, x-display-format, x-list-columns, x-label,
x-order, x-hidden, x-filterable, x-sortable, x-autocomplete), auth-server
x-* securityScheme wiring, shared error responses
- config/init/main: REPO_BACKEND knob, load_dotenv before spec build
Verified: 7/7 tests pass; live smoke test (/health ok, 401 without token)
Vishesh 'ironeagle' Bangotra
e88005d936