Collapse the three data layers into one. app/db.py now exposes a single
Base, a cached engine bound to app_database_url with SQLite WAL enabled, and
get_engine/get_session_local/reset_db_caches/get_db_session. Delete
app/auth_db.py, app/poo_db.py and app/models/base.py. All models (auth,
config, public_ip, location, poo) inherit the one Base and register on a
single metadata. Dependencies converge to a single get_db; all routes use it.
Also update the alembic env.py files (app/location/poo) and tests that
imported the removed modules so the suite stays green, and drop the obsolete
test_legacy_style_location_db test whose flow (app reading a separate location
DB) no longer exists. Location/poo Alembic chains, adopt scripts and adoption
tests remain for M1-T04; config fields remain for M1-T05.
pytest 109 passed; ruff clean (pre-existing only); WAL verified; single
Base.metadata holds all seven tables.
scripts/migrate_legacy_data.py copies rows from the legacy locationRecorder.db
/ pooRecorder.db into the unified app DB's location / poo_records tables using
ATTACH + INSERT OR IGNORE (idempotent via PK-conflict skip; explicit columns,
never SELECT *). After copy it reconciles every source row against the target
and raises / exits non-zero on any shortfall. Missing legacy files are a safe
no-op (skipped); --dry-run writes nothing. Not part of the Alembic chain; run
manually once at cut-over. Never deletes or overwrites any file.
Validated end-to-end on copies of the real production DBs: dry-run reported
75103 location + 874 poo rows and wrote nothing; the real run copied all rows
with reconciliation passing; a second run copied 0 (idempotent).
tliu93