Deduplicate ISO-timestamp parsing and document the new device type (review follow-up, issue #131)

- vacuum_station._parse_iso_utc was a verbatim copy of
  water_purifier._parse_iso_utc; promoted to common.parse_iso_utc and
  pointed both families at it. Also made it tzinfo-aware rather than
  unconditionally overwriting with UTC -- harmless today since every
  dump seen is a bare or Z-suffixed UTC timestamp, but a board that
  ever emits a real offset would otherwise have it silently clobbered.
- Added the new vacuum_station type to the README's supported-appliance
  table, and noted that combi microwaves route through the oven
  registry.

README.md

@@ -25,7 +25,7 @@ Your state stays on your LAN: HA talks to the appliance over a direct DTLS sessi
 | Air purifier | `by_type/air_purifier.py` |
 | Dehumidifier | `by_type/dehumidifier.py` |
 | Dryer | `by_type/dryer.py` |
-| Oven | `by_type/oven.py` |
+| Oven (including combi microwaves) | `by_type/oven.py` |
 | Gas cooktop (read-only burner status) | `by_type/cooktop.py` |
 | Range hood | `by_type/range_hood.py` |
 | Range | `by_type/range.py` |
@@ -33,6 +33,7 @@ Your state stays on your LAN: HA talks to the appliance over a direct DTLS sessi
 | Refrigerator | `by_type/refrigerator.py` |
 | Washer | `by_type/washer.py` |
 | Water purifier | `by_type/water_purifier.py` |
+| Vacuum clean/auto-empty station | `by_type/vacuum_station.py` |
 
 Each registry composes shared and family-specific `Capability` objects from `registry/capabilities/`; those modules document the individual resources/entities in more depth than a README table can stay current with.
 

custom_components/localthings/registry/capabilities/common.py

@@ -10,6 +10,8 @@ against live device dumps:
   /water/consumption/vs/0   -> x.com.samsung.da.cumulativeWater
   /filter/waterfilter/vs/0  -> x.com.samsung.da.filterUsage / filterStatus
 """
+from datetime import datetime, timezone
+
 from ..capability import Capability
 from ..entities import (
     BinarySensorDesc, ButtonDesc, SelectDesc, SensorDesc, SwitchDesc,
@@ -40,6 +42,22 @@ def wh_to_kwh(v):
     return round(n / 1000.0, 2) if n is not None else None
 
 
+def parse_iso_utc(raw):
+    """ISO datetime defaulting to UTC when the string carries no timezone
+    of its own (this integration's convention for other bare ISO datetime
+    fields -- see washer.py's drum-clean-log comment). A few boards do
+    ship a 'Z'/offset suffix (fromisoformat parses that natively since
+    Python 3.11) -- only fill in UTC when parsing left the result naive,
+    rather than unconditionally overwriting whatever offset was parsed."""
+    if not raw:
+        return None
+    try:
+        dt = datetime.fromisoformat(raw)
+    except ValueError:
+        return None
+    return dt if dt.tzinfo is not None else dt.replace(tzinfo=timezone.utc)
+
+
 def filter_usage_percent(rep):
     """Filter usage as a percentage of rated capacity. Several families
     (AC, air purifier) report `filterUsage` as a raw count in

custom_components/localthings/registry/capabilities/vacuum_station.py

@@ -15,23 +15,9 @@ docstring for that rule).
 
 Resources verified against the issue #131 diagnostics dump.
 """
-from datetime import datetime, timezone
-
 from ..capability import Capability
 from ..entities import BinarySensorDesc, SelectDesc, SensorDesc, SwitchDesc
-from .common import int_or_none
+from .common import int_or_none, parse_iso_utc as _parse_iso_utc
-
-
-def _parse_iso_utc(raw):
-    """Bare ISO datetime with no timezone field alongside it -- treated as
-    UTC, matching this integration's convention for other bare ISO datetime
-    fields (see water_purifier.py's own _parse_iso_utc)."""
-    if not raw:
-        return None
-    try:
-        return datetime.fromisoformat(raw).replace(tzinfo=timezone.utc)
-    except ValueError:
-        return None
 
 
 DUSTBAG = Capability(

custom_components/localthings/registry/capabilities/water_purifier.py

@@ -3,23 +3,9 @@ issue #90, model TP2X_WATERPURIFIER_20K).
 
 Resources verified against the issue #90 diagnostics dump.
 """
-from datetime import datetime, timezone
-
 from ..capability import Capability
 from ..entities import BinarySensorDesc, NumberDesc, SelectDesc, SensorDesc, SwitchDesc
-from .common import int_or_none
+from .common import int_or_none, parse_iso_utc as _parse_iso_utc
-
-
-def _parse_iso_utc(raw):
-    """Bare ISO datetime with no timezone field alongside it -- treated as
-    UTC, matching this integration's convention for other bare ISO datetime
-    fields (see washer.py's drum-clean-log comment)."""
-    if not raw:
-        return None
-    try:
-        return datetime.fromisoformat(raw).replace(tzinfo=timezone.utc)
-    except ValueError:
-        return None
 
 
 DISPENSE = Capability(