chore(semantics): add v6 release gate pipeline

- Add reproducible v6 boundary, blessing, and consensus-adjudication
  corpora, plus the tiny-transformer trainer and v6 release-gate
  evaluator that gate every candidate on the deployed baselines.
- Wire consensus-label merging, product-policy anchor evaluation, and
  sealed blessing benchmark review with their pytest coverage.
- Refresh open-training corpus generation, iterative retraining runner,
  and random-holdout evaluation so v6 candidates can be benchmarked
  end-to-end.

ModelTraining/ClipboardSemantics/Consensus/adjudication-instructions-v2.md

@@ -0,0 +1,56 @@
+# Clipboard semantic evidence adjudication v2
+
+Review only the fields listed in `unresolvedFields`. Judge from the text itself;
+do not inspect previous model votes, source labels, or another adjudicator.
+Apply the product-approved boundaries from `labeling-instructions-v3.md`.
+
+Return one JSON object per input record:
+
+```json
+{
+  "id": "same id",
+  "recordDisposition": "keep",
+  "dispositionConfidence": 0.98,
+  "dispositionEvidence": "send the report",
+  "resolutions": {
+    "task": "true",
+    "ambiguous": "false"
+  },
+  "confidence": {
+    "task": 0.97,
+    "ambiguous": 0.94
+  },
+  "evidence": {
+    "task": "send the report",
+    "ambiguous": "by Friday"
+  }
+}
+```
+
+Requirements:
+
+- `recordDisposition` must be `keep` or `exclude-device-command`.
+- Use `exclude-device-command` only when the text is clearly addressed to a
+  device, app, search engine, or virtual assistant. Do not use it for an
+  ordinary request to another person.
+- `dispositionConfidence` must be between 0 and 1.
+- `dispositionEvidence` must be a short exact quote copied from the text.
+- `resolutions`, `confidence`, and `evidence` must contain exactly the fields in
+  `unresolvedFields`, even when the record is marked for exclusion.
+- Intent and flag values are `true`, `false`, or `unknown`.
+- Sentiment values are `positive`, `neutral`, `negative`, or `unknown`.
+- Field evidence must be a short exact quote copied from the input text.
+- Use `unknown` when the text alone does not justify a decision.
+- Confidence is per field and must be between 0 and 1.
+- Do not output explanations, markdown, or additional fields.
+
+Critical product decisions:
+
+- An invitation question is `invitation=true`, `question=false`, and normally
+  `replyableMessage=true`.
+- An explicit self-reminder is `followUpReminder=true`, `task=false`.
+- A first-person need implying action is `task=true`.
+- A problem is not a complaint unless dissatisfaction, criticism, or objection
+  is explicitly expressed.
+- Generic encouragement or happiness is not a blessing; require an explicit
+  wish, prayer, congratulation, or conventional blessing.