K12 (healers attempts): mesh-healers says attempt-changed, keyed by condition and attempt

attempt-changed.<condition>.<attempt>, kept last per subject, 7 days and 16 MiB, its body the attempt's value whole with
until, or removed. Generated code waits for K21.

Builds: design 47 G §541, §665

Claude-Session: https://claude.ai/code/session_01JG73KEq4zoDfM9WtYpcQgZ

health-and-repair/seats/mesh-healers/fixtures/events.json

@@ -0,0 +1,26 @@
+[
+  {
+    "name": "an attempt begun, said with its end (design 47 G 665)",
+    "of": "event:attempt-changed",
+    "subject": "mesh.seat.mesh-healers.event.attempt-changed.c-1.a-1",
+    "given": {
+      "healer": "directory",
+      "condition": "module.mesh-host.ace.directory-used-as-found",
+      "kind": "directory-used-as-found",
+      "budget-key": "module.mesh-host.ace.directory-used-as-found",
+      "act": "hand-over",
+      "outcome": "acting",
+      "begun": "2026-11-11T10:00:00Z",
+      "until": "2026-11-11T12:00:00Z"
+    }
+  },
+  {
+    "name": "an attempt ended by its healer",
+    "of": "event:attempt-changed",
+    "subject": "mesh.seat.mesh-healers.event.attempt-changed.c-1.a-1",
+    "given": {
+      "condition": "module.mesh-host.ace.directory-used-as-found",
+      "removed": true
+    }
+  }
+]

health-and-repair/seats/mesh-healers/seat.json

@@ -135,6 +135,66 @@
           "outcome"
         ]
       }
+    },
+    {
+      "name": "attempt-changed",
+      "subject": "attempt-changed.<condition>.<attempt>",
+      "keep": {
+        "max-age-days": 7,
+        "max-mib": 16,
+        "last-per-subject": true
+      },
+      "body": {
+        "type": "object",
+        "description": "an attempt as the attempts state holds it, whole, with until, or removed: true when the healer ends it; said again for every open attempt at the healers' start (design 47 G 541, 665)",
+        "properties": {
+          "healer": {
+            "type": "string"
+          },
+          "condition": {
+            "type": "string"
+          },
+          "kind": {
+            "type": "string"
+          },
+          "budget-key": {
+            "type": "string",
+            "description": "what the budget counts by: the condition's key unless the healer says another"
+          },
+          "act": {
+            "type": "string"
+          },
+          "outcome": {
+            "type": "string",
+            "enum": [
+              "acting",
+              "acted",
+              "failed",
+              "escalated"
+            ]
+          },
+          "said": {
+            "type": "string"
+          },
+          "begun": {
+            "type": "string",
+            "format": "date-time"
+          },
+          "finished": {
+            "type": "string",
+            "format": "date-time"
+          },
+          "until": {
+            "type": "string",
+            "format": "date-time",
+            "description": "the end of that key's lifetime, which the keeper drops the attempt at on its own clock"
+          },
+          "removed": {
+            "type": "boolean",
+            "description": "true when the healer ends the attempt"
+          }
+        }
+      }
     }
   ],
   "family": {