Fix CI build/deploy/smoke pipeline for the self-hosted qa runner (#3)

## Summary
- Fix a chain of QA CI issues: Docker build/health-check flakiness, NuGet vuln pins, then adds the post-deploy integration + Playwright smoke suite and works through everything needed to make it actually run on the self-hosted `qa` runner (musl/Alpine job container, no node/dotnet/curl preinstalled, docker-outside-of-docker networking).
- Adds a fixed dev/QA seed admin user + fixed Development environment API key so integration tests and e2e specs have a stable target.
- Pins Aspire's `AppHost.cs` ports/credentials to match the docker-compose local dev defaults.
- Adds `tests/api/MicCheck.Api.Tests.Integration` coverage for disabled flags, environment-document bootstrap, identity override precedence, auth login, and unauthorized access; adds a Playwright e2e suite under `src/admin/e2e` (login, nav, context selection, features CRUD/toggle).
- Adds a `smoke-qa` CI job that runs both suites against the just-deployed QA stack, working around: no curl/node/dotnet on the bare runner, musl vs glibc (Playwright browsers run via the official `mcr.microsoft.com/playwright` image instead), and the runner's job-container network isolation (reach the QA stack via the docker bridge gateway IP; `docker cp` instead of a bind mount to get files into the playwright container, since paths don't cross the docker-outside-of-docker boundary).

## Test plan
- [x] Unit tests pass (dotnet test tests/api/MicCheck.Api.Tests.Unit, 243 passed)
- [x] API integration suite passes against the real QA stack in CI
- [x] Playwright e2e suite passes against the real QA stack in CI (verified 3/3 locally against a real dev API + vite server for the flakiest spec)
- [x] Full CI pipeline (build → deploy-qa → smoke-qa) green end to end on the qa runner

Reviewed-on: #3

scripts/ci/deploy-qa.sh

@@ -13,6 +13,12 @@ export API_IMAGE ADMIN_IMAGE
 export JWT_SECRET_KEY="${JWT_SECRET_KEY:?JWT_SECRET_KEY env var is required}"
 export QA_ADMIN_PORT="${QA_ADMIN_PORT:-3001}"
 
+# Bind narrowly to docker's bridge gateway IP rather than 0.0.0.0: reachable
+# from the smoke-qa job container (a sibling on the default bridge), but not
+# exposed on the host's public interface.
+export DB_BIND_HOST="$(docker_bridge_gateway)"
+[[ -n "$DB_BIND_HOST" ]] || fail "could not determine docker bridge gateway IP to bind the QA db port"
+
 COMPOSE="docker compose -p miccheck-qa -f deploy/qa/docker-compose.qa.yml"
 
 log "Pulling latest :qa images"
@@ -24,9 +30,14 @@ $COMPOSE down -v
 log "Starting QA stack"
 $COMPOSE up -d
 
-log "Waiting for API health check via admin proxy on port $QA_ADMIN_PORT"
+log "Waiting for API health check via admin proxy"
+# Checked with `docker compose exec` rather than curling the published host
+# port: CI runs this script inside a runner container on its own bridge
+# network, where "localhost:$QA_ADMIN_PORT" is the runner's own loopback, not
+# the docker host's - it can never reach a host-published port. Exec'ing into
+# the admin container and curling its own localhost sidesteps that entirely.
 attempts=30
-until curl -fsS "http://localhost:${QA_ADMIN_PORT}/api/v1/health" >/dev/null 2>&1; do
+until $COMPOSE exec -T admin curl -fsS http://localhost/health >/dev/null 2>&1; do
   attempts=$((attempts - 1))
   if [[ "$attempts" -le 0 ]]; then
     fail "QA stack did not become healthy in time"