M1-T04: converge startup chain onto the single app DB

run_all_migrations() now adopts/initializes only the app DB and returns
{'app': ...}. app/main.py drops the location/poo readiness checks
(ensure_location_db_ready / ensure_poo_db_ready) and their imports;
ensure_runtime_dirs only provisions the app DB path; lifespan still
fail-closes on a missing/unmanaged app DB. Delete the retired
location/poo adopt scripts and the alembic_location / alembic_poo
chains. Update tests to single-DB expectations and drop the obsolete
location/poo adoption + readiness tests.

pytest 95 passed; ruff clean (pre-existing only); a fresh app DB
initialized via scripts.run_migrations contains location + poo_records.

tests/test_poo.py

@@ -1,17 +1,8 @@
-from pathlib import Path
-import sqlite3
-
 import pytest
 from sqlalchemy import text
 
 from app.config import Settings, get_settings
 from app.dependencies import get_app_settings, get_homeassistant_client
-from scripts.poo_db_adopt import (
-    EXPECTED_USER_VERSION,
-    POO_BASELINE_REVISION,
-    PooDatabaseAdoptionError,
-    adopt_or_initialize_poo_db,
-)
 
 
 class _FakeHomeAssistantClient:
@@ -153,96 +144,3 @@ def test_poo_latest_endpoint_returns_ok_when_no_record_exists(poo_client_with_ov
     assert response.text == ""
 
 
-def test_poo_db_adoption_initializes_new_db(tmp_path: Path) -> None:
-    database_path = tmp_path / "new_poo.db"
-
-    result = adopt_or_initialize_poo_db(f"sqlite:///{database_path}")
-
-    assert result == "initialized"
-    assert database_path.exists()
-
-    conn = sqlite3.connect(database_path)
-    try:
-        revision = conn.execute("SELECT version_num FROM alembic_version").fetchone()[0]
-        poo_table = conn.execute(
-            "SELECT name FROM sqlite_master WHERE type = 'table' AND name = 'poo_records'"
-        ).fetchone()
-    finally:
-        conn.close()
-
-    assert revision == POO_BASELINE_REVISION
-    assert poo_table is not None
-
-
-def test_poo_db_adoption_validates_and_stamps_legacy_db(tmp_path: Path) -> None:
-    database_path = tmp_path / "legacy_poo.db"
-    conn = sqlite3.connect(database_path)
-    conn.execute(
-        """
-        CREATE TABLE poo_records (
-          timestamp TEXT NOT NULL,
-          status TEXT NOT NULL,
-          latitude REAL NOT NULL,
-          longitude REAL NOT NULL,
-          PRIMARY KEY (timestamp)
-        )
-        """
-    )
-    conn.execute(f"PRAGMA user_version = {EXPECTED_USER_VERSION}")
-    conn.commit()
-    conn.close()
-
-    result = adopt_or_initialize_poo_db(f"sqlite:///{database_path}")
-
-    assert result == "adopted"
-
-    conn = sqlite3.connect(database_path)
-    try:
-        revision = conn.execute("SELECT version_num FROM alembic_version").fetchone()[0]
-    finally:
-        conn.close()
-
-    assert revision == POO_BASELINE_REVISION
-
-
-def test_poo_db_adoption_fails_closed_on_schema_mismatch(tmp_path: Path) -> None:
-    database_path = tmp_path / "bad_poo_schema.db"
-    conn = sqlite3.connect(database_path)
-    conn.execute(
-        """
-        CREATE TABLE poo_records (
-          timestamp TEXT NOT NULL,
-          status TEXT NOT NULL,
-          latitude REAL NOT NULL,
-          PRIMARY KEY (timestamp)
-        )
-        """
-    )
-    conn.execute(f"PRAGMA user_version = {EXPECTED_USER_VERSION}")
-    conn.commit()
-    conn.close()
-
-    with pytest.raises(PooDatabaseAdoptionError, match="schema does not match"):
-        adopt_or_initialize_poo_db(f"sqlite:///{database_path}")
-
-
-def test_poo_db_adoption_fails_closed_on_user_version_mismatch(tmp_path: Path) -> None:
-    database_path = tmp_path / "bad_poo_user_version.db"
-    conn = sqlite3.connect(database_path)
-    conn.execute(
-        """
-        CREATE TABLE poo_records (
-          timestamp TEXT NOT NULL,
-          status TEXT NOT NULL,
-          latitude REAL NOT NULL,
-          longitude REAL NOT NULL,
-          PRIMARY KEY (timestamp)
-        )
-        """
-    )
-    conn.execute("PRAGMA user_version = 999")
-    conn.commit()
-    conn.close()
-
-    with pytest.raises(PooDatabaseAdoptionError, match="Expected PRAGMA user_version"):
-        adopt_or_initialize_poo_db(f"sqlite:///{database_path}")