feat(homeassistant): it shows system problems and installs updates on a weekly slot, and leaves device readings alone (#6748, #6749, #6747)

The connection's job is keeping Home Assistant running. Each poll now reads open
repairs, Supervisor health, disk, recovery mode and add-ons that should be running
over its websocket, for the page, the overview and the problems_open, disk_free_pct
and update_failed metrics. That needs a websocket client, so websockets joins the
dependencies.

A weekly slot, set on the page or through MCP and off until then, installs add-ons,
then Core, then the OS, each after its own confirmed backup, ending at the first
failure. The slot arithmetic moves from the host agent's cadence to steward.core.weekly
so both share it.

The device scrape goes: the page's Metrics section and a target's token_from from
4c9ed02 are removed, and a migration deletes targets using it, as they'd otherwise ask
with no token. A refused token still stops a scrape.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

plugins/homeassistant/scheduler.py

@@ -10,9 +10,9 @@ from sqlalchemy import select
 
 from steward.core.scheduler import ScheduledTask
 
-from . import client
-from .models import HomeAssistantConnection
-from .service import RESOURCE, SOURCE, backup_age_hours, installable, read_snapshot
+from . import client, schedule
+from .models import HomeAssistantConnection, HomeAssistantSchedule, HomeAssistantUpdate
+from .service import RESOURCE, SOURCE, backup_age_hours, installable, read_health, read_snapshot
 from .updates import advance
 
 if TYPE_CHECKING:
@@ -36,7 +36,7 @@ def make_tick_task(app: "Quart") -> ScheduledTask:
         if busy.locked():
             return
         async with busy:
-            for step in (poll, advance):
+            for step in (poll, advance, schedule.step):
                 try:
                     await asyncio.wait_for(step(app), STEP_DEADLINE_SECONDS)
                 except TimeoutError:
@@ -56,7 +56,15 @@ def is_due(connection, now: datetime) -> bool:
     return (now - connection.last_polled_at).total_seconds() >= POLL_SECONDS - TICK_SECONDS / 2
 
 
-async def poll(app: "Quart", transport=None) -> None:
+async def update_failed(session) -> bool:
+    """Whether the newest update failed, or the schedule couldn't start one."""
+    stopped = (await session.execute(select(HomeAssistantSchedule.stopped))).scalars().first()
+    newest = (await session.execute(select(HomeAssistantUpdate.state).order_by(
+        HomeAssistantUpdate.started_at.desc()).limit(1))).scalars().first()
+    return bool(stopped) or newest == "failed"
+
+
+async def poll(app: "Quart", transport=None, connect=None) -> None:
     from steward.core.alerts import MetricBatch
 
     now = datetime.now(timezone.utc)
@@ -64,12 +72,17 @@ async def poll(app: "Quart", transport=None) -> None:
         connection = (await session.execute(select(HomeAssistantConnection))).scalars().first()
     if connection is None or not is_due(connection, now):
         return
-    snapshot, error, refused = None, None, False
+    snapshot, health, error, refused = None, None, None, False
     try:
         token = await client.access_token(connection, transport)
         snapshot = read_snapshot(await client.read_states(connection.url, token, connection.verify_tls, transport))
+        try:
+            health = read_health(await client.read_system(connection.url, token, connection.verify_tls, connect))
+        except client.Unreachable as exc:
+            # Updates and backups were read, so it's answering. The last report stands, and says it's old.
+            health = {**(connection.health or {}), "error": str(exc)}
     except client.Refused as exc:
-        error, refused = str(exc), True
+        snapshot, error, refused = None, str(exc), True
     except client.Unreachable as exc:
         error = str(exc)
     async with app.db_sessionmaker() as session:
@@ -83,7 +96,7 @@ async def poll(app: "Quart", transport=None) -> None:
                 batch.add(source_module=SOURCE, resource_name=RESOURCE, metric_name="is_up", value=0.0, recorded_at=now)
             else:
                 row.last_ok_at = now
-                row.updates, row.backup = snapshot["updates"], snapshot["backup"]
+                row.updates, row.backup, row.health = snapshot["updates"], snapshot["backup"], health
                 batch.add(source_module=SOURCE, resource_name=RESOURCE, metric_name="is_up", value=1.0, recorded_at=now)
                 batch.add(source_module=SOURCE, resource_name=RESOURCE, metric_name="updates_waiting",
                           value=len(installable(row)), recorded_at=now)
@@ -91,4 +104,13 @@ async def poll(app: "Quart", transport=None) -> None:
                 if age is not None:
                     batch.add(source_module=SOURCE, resource_name=RESOURCE, metric_name="backup_age_hours",
                               value=age, recorded_at=now)
+                if not health.get("error"):
+                    if health["repairs_read"]:
+                        batch.add(source_module=SOURCE, resource_name=RESOURCE, metric_name="problems_open",
+                                  value=len(health["problems"]), recorded_at=now)
+                    if health["disk_free_pct"] is not None:
+                        batch.add(source_module=SOURCE, resource_name=RESOURCE, metric_name="disk_free_pct",
+                                  value=health["disk_free_pct"], recorded_at=now)
+                batch.add(source_module=SOURCE, resource_name=RESOURCE, metric_name="update_failed",
+                          value=1.0 if await update_failed(session) else 0.0, recorded_at=now)
             await batch.record(session)