Implements GET/DELETE /api/library, POST /api/library/{id}/reingest,
POST /api/library/scan, and GET /api/library/{id}/status. Adds FastAPI
app factory with lifespan migrations, BM25 singleton wiring, get_db
dependency, ingest task registry with cf-orch/BackgroundTasks fallback,
and placeholder search/chat routers. All 5 new tests pass (14 total).
Adds pyproject.toml, environment.yml, Dockerfile, docker/web (Vue+nginx),
compose.yml, compose.override.yml.example, manage.sh, .env.example,
.gitignore, and config stubs for the pagepiper self-hosted PDF library tool.
Port 8521. No secrets committed.
