merge(learn): harvest signals for the decision engine (decision-engine task 5)

Verify a/b + agree on 150 labelled units ($2.54 attributed), model roles on 799
files ($1.40), engine features for 682 of 686 pair sides; 1,712 feature records.

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo

benchmarks/measurements/2026-09-08-module-audit.json

@@ -1,7 +1,7 @@
 {
-  "modules": 153,
+  "modules": 154,
   "counts": {
-    "load_bearing": 146,
+    "load_bearing": 147,
     "standalone_capability": 7
   },
   "orphaned": [],
@@ -362,9 +362,11 @@
         "learn.excerpt",
         "learn.features",
         "learn.folds",
+        "learn.labels",
         "learn.program",
         "learn.retrieve",
         "learn.roles",
+        "plane.harvest",
         "plane.tasks.features",
         "plane.tasks.remember",
         "plane.tasks.roles"
@@ -432,7 +434,8 @@
       "reason": "reachable from gate, map_gate, pair_gate or the CLI",
       "importers": [
         "learn.embeddings",
-        "learn.examples"
+        "learn.examples",
+        "learn.labels"
       ]
     },
     {
@@ -468,7 +471,8 @@
         "learn.evaluate",
         "learn.examples",
         "learn.excerpt",
-        "learn.retrieve"
+        "learn.retrieve",
+        "plane.harvest"
       ]
     },
     {
@@ -831,6 +835,7 @@
         "learn.labels",
         "model.candidates",
         "pair_gate",
+        "plane.harvest",
         "plane.tasks.loop"
       ]
     },
@@ -849,6 +854,7 @@
         "plane.egress",
         "plane.engine_alerts",
         "plane.generate",
+        "plane.harvest",
         "plane.memory",
         "plane.reconciler",
         "plane.router",
@@ -900,6 +906,15 @@
       "module": "plane.generate",
       "classification": "load_bearing",
       "reason": "ai-service-plane task 7: an increment's Workspaces, per-case Tasks and Run from a recorded set",
+      "importers": [
+        "cli",
+        "plane.harvest"
+      ]
+    },
+    {
+      "module": "plane.harvest",
+      "classification": "load_bearing",
+      "reason": "reachable from gate, map_gate, pair_gate or the CLI",
       "importers": [
         "cli"
       ]
@@ -912,6 +927,7 @@
         "learn.cli",
         "plane.egress",
         "plane.generate",
+        "plane.harvest",
         "plane.reconciler",
         "plane.router",
         "plane.runner",
@@ -940,6 +956,7 @@
       "reason": "ai-service-plane Req 3.1-3.5, 7.3: ax-backed Run execution, status attribution and doctor; `ousast plane`",
       "importers": [
         "plane.generate",
+        "plane.harvest",
         "plane.memory",
         "plane.workspaces"
       ]
@@ -971,6 +988,7 @@
         "learn.roles",
         "plane.engine_alerts",
         "plane.generate",
+        "plane.harvest",
         "plane.memory",
         "plane.tasks.agree",
         "plane.tasks.alerts",
@@ -1027,6 +1045,7 @@
         "learn.labels",
         "learn.roles",
         "plane.generate",
+        "plane.harvest",
         "plane.tasks.alerts",
         "plane.tasks.features",
         "plane.tasks.remember",
@@ -1037,7 +1056,9 @@
       "module": "plane.tasks.roles",
       "classification": "load_bearing",
       "reason": "learned-decision-engine Req 8.1: model role classification per file chunk (model_sinks.py moved in); its Run template comes with the harvest (task 5)",
-      "importers": []
+      "importers": [
+        "plane.harvest"
+      ]
     },
     {
       "module": "plane.tasks.verify",
@@ -1045,6 +1066,7 @@
       "reason": "ai-service-plane Req 5.3/2.1-2.3/7.2: the batched hunt with known callers, metered and resumable per file hunt",
       "importers": [
         "plane.generate",
+        "plane.harvest",
         "plane.tasks.agree",
         "plane.tasks.roles"
       ]
@@ -1105,6 +1127,7 @@
         "model.partitions",
         "model.scan",
         "pairs",
+        "plane.harvest",
         "plane.tasks.alerts",
         "plane.tasks.features",
         "plane.tasks.repo_facts",