Score a forecast only when the relay matched its plan in time, not just in share

Reproduced: a forecast planning 15 minutes of heat was scored although the
relay was on for 12 (the 0.4.1 rule allowed 20 % per 15-minute block), and
the same on-time placed elsewhere in a block passed as well.

- The relay's on-time per poll interval, integrated at its own switch
  times, is compared with the plan block by block up to each horizon: the
  deviation is the time the relay spent in another state than planned.
  Unobserved relay time counts as possible deviation.
- Matched (at most 2 minutes, worst case): Forecast Error figures.
  Approximate (at most 5 minutes, at most 2 of them unobserved): separate
  approximate_stats. Counterfactual (more than 5 minutes seen): counted, not
  scored. Incomplete otherwise, by reason: relay history, assumed inputs at
  forecast time (an unknown window or electrical heat), no poll near the
  due time, or a missing reading.
- 2 minutes of unplanned boiler heat move a room by roughly half a 0.1 °C
  sensor step for the learned heat coefficients (0.05-0.12 °C per 5
  minutes); 5 minutes by about one step.
- Stored ledger statistics are versioned (2); 0.4.1 statistics used the
  looser rule and are dropped.

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

custom_components/heating_mpc/coordinator.py

@@ -895,9 +895,16 @@ class HeatingMPCCoordinator(DataUpdateCoordinator[dict[str, Any]]):
             _LOGGER.warning("MPC prediction failed: %s", err)
             status["status"] = "prediction_error"
             return status
+        # Inputs the forecast had to assume: such forecasts are not compared with reality.
+        uncertain = [f"window: {name}" for room in vals
+                     for name in (vent_inputs.get(room) or {}).get("unknown_windows", [])]
+        uncertain += [f"electrical heat: {self.zones[room].name}" for room in vals
+                      if internal[room] is None and room in self.extended
+                      and ZoneModel(self.learners[room], self.extended[room]).uses_extended]
         self._forecasts.record(now.timestamp(), vals, output["trajectory_15min"], output["plan_15min"],
                                self._revision(), {
             "strategy": "mpc_plan", "outside": outside, "wind": weather.get("wind"),
+            "uncertain_inputs": uncertain,
             "internal_half_life_minutes": float(self.config.get(CONF_INTERNAL_HALF_LIFE, 30)),
             "window_open_minutes": float(self.config[CONF_WINDOW_OPEN_MINUTES]),
             "internal_kw": {room: internal[room] for room in vals},