Release 0.2.3

Bump the manifest to 0.2.3 for the stale-room policy: unusable room
sensors are left out with weights re-normalized, and an opt-in checkbox
keeps a stale sensor's last value for up to 24 hours. 0.2.2 was never
deployed, so the changelog marks it as such and the 0.2.3 notes point
0.2.1 users at both entries. ROADMAP and AUDIT record the decision and
the open control-design questions (minimum weight coverage, outdoor
temperature outages).

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

CHANGELOG.md

@@ -2,7 +2,38 @@
 
 Engineering findings and test evidence behind each change are in [AUDIT.md](AUDIT.md).
 
-## 0.2.2 — 2026-10-26
+## 0.2.3 — 2026-10-26
+
+A stale or failed room sensor no longer pauses the whole integration. Still
+**observation-only**. Upgrading from 0.2.1 (0.2.2 was not deployed): follow the
+0.2.2 upgrade notes below as well.
+
+### Changed
+
+- A room sensor that is stale, unavailable, missing or invalid is now **left out**
+  instead of pausing everything: the weighted temperature, learning and forecasts
+  continue with the other rooms, whose comfort weights are re-normalized. Learning
+  and forecasts pause only if no room is usable, or if the relay, thermostat or
+  outdoor temperature is missing. Readiness considers only the rooms used.
+
+### Added
+
+- Checkbox **Keep using the last value of a room sensor that stopped reporting**
+  (setup and Configure, default off), for sensors that report only when the value
+  changes. A stale sensor's last value is then still used, for up to 24 hours
+  without a report. Unavailable or invalid sensors are always left out.
+- Status attributes `excluded_rooms` and `weight_coverage` (share of the total
+  comfort weight covered by the rooms used), and a per-room `used` flag in
+  `input_quality`.
+
+### Upgrade notes
+
+- The new checkbox appears in **Configure**; existing installations start with it
+  off. If a room is often listed in `excluded_rooms` while its temperature is
+  steady, either raise that room's report-age limit or turn the checkbox on.
+- Rollback to 0.2.2 or 0.2.1 is safe; older versions ignore the new setting.
+
+## 0.2.2 — 2026-10-26 (not deployed)
 
 Reliability release (Milestone 0). Still **observation-only**: the integration never
 calls the relay, the thermostat or any other service. No new options or UI text;