UPS: ups_pct_source and ups_charge_ah (counted charge); host.ndjson in capture sessions

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DDwfd6Ki8UfG4hK6W5YpJz

schema/signals.json

@@ -760,12 +760,28 @@
       "unit": "percent",
       "type": "number",
       "source": "host",
-      "description": "UPS charge estimate from cell voltage, corrected for load. An estimate, steadiest at rest",
+      "description": "UPS charge: counted from the current since the charger last stopped at full when ups_pct_source is 'counted'; otherwise the estimate from cell voltage, corrected for load, steadiest at rest",
       "range": [
         0,
         100
       ]
     },
+    "ups_pct_source": {
+      "unit": "",
+      "type": "string",
+      "source": "host",
+      "description": "Where ups_battery_pct comes from: 'counted' (current integrated since the last full charge, against the configured capacity) or 'voltage' (no full charge seen since the count was lost: pack out, Orin off a while, capacity changed)"
+    },
+    "ups_charge_ah": {
+      "unit": "Ah",
+      "type": "number",
+      "source": "host",
+      "description": "UPS charge counted since the last full charge; absent until there has been one",
+      "range": [
+        0,
+        20
+      ]
+    },
     "ups_state": {
       "unit": "",
       "type": "string",