Threads, commands and labels on the new loop (M2.3)

- Commands that name their item ("go #14", "abandon #14", "stop #14")
  apply to it wherever they're said; go, approve and abandon alone at top
  level are asked about (L5). stop is never taken as an answer.
- A plain-language reply to a restatement is read by GoAheadReader, one
  model call that agrees only on a clear yes; questions never reach it. The
  agent says "taking that as a go-ahead on rev-N" first, bound to the
  revision on screen at arrival (L3, L5, D1).
- Labels steer (D1): `bug` goes ahead after tuning.loop.bug_grace_s
  (default 600 s) unless the operator replies; `discuss` isn't offered
  restate until the operator has spoken; `bug`, `discuss` and `design` add
  to the driver's instructions. A restatement asks no questions.

Tests: label and command unit tests, the property walk with labelled
issues, plain yeses, named gos and time passing (grace_only_unanswered,
discuss_talks_first), and e2e tests for a bug proceeding after its grace
period and a plain-language go-ahead.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PPQ14L3LikyefCMFBqEbKE

nisse-dev/src/nisse_dev/loop/reader.py

@@ -0,0 +1,81 @@
+"""Reading a plain-language reply as a go-ahead (L5, D1).
+
+"Yep, that's it" in reply to a restatement may be taken as `go`, because a
+wrong reading costs only time. One short model call decides, and it decides
+conservatively: only a clear yes counts. A question is never a go-ahead and
+never reaches the model (L5: questions never change state).
+
+The driver's model reads for now; the classifier role takes over in M2.6.
+"""
+
+from typing import Any
+
+from nisse_dev.canonical import StoredEvent, ToolCall, UserMessage
+from nisse_dev.llm import LLMClient, LLMError
+
+VERDICT = {
+    "type": "function",
+    "function": {
+        "name": "verdict",
+        "description": "Your reading of the operator's reply.",
+        "parameters": {
+            "type": "object",
+            "properties": {
+                "answer": {
+                    "type": "string",
+                    "enum": ["yes", "no", "unclear"],
+                    "description": "yes: a clear go-ahead on the proposal as it "
+                    "stands. no: it asks for changes, disagrees or says to wait. "
+                    "unclear: anything else.",
+                }
+            },
+            "required": ["answer"],
+        },
+    },
+}
+
+SYSTEM = """You read one reply from an operator to a software agent. The agent
+put a proposal up for agreement; decide whether the reply clearly agrees to the
+proposal as it stands, so the agent may start. A reply that asks for any
+change, asks a question, adds a condition, or is about something else is not a
+go-ahead. When in doubt, it is not. Answer with the verdict tool."""
+
+
+def is_question(text: str) -> bool:
+    return text.rstrip().endswith("?")
+
+
+class GoAheadReader:
+    def __init__(self, client: LLMClient, model: str) -> None:
+        self._client = client
+        self._model = model
+
+    def agrees(self, proposal: str, reply: str) -> bool:
+        if is_question(reply):
+            return False
+        prompt = f"The proposal:\n\n{proposal}\n\nThe operator's reply:\n\n{reply}"
+        try:
+            produced = self._client.complete(
+                [
+                    StoredEvent(
+                        id=0,
+                        ts="",
+                        event=UserMessage(text=prompt, source="go-ahead reader"),
+                        actor="orchestrator",
+                    )
+                ],
+                tools=[VERDICT],
+                model=self._model,
+                system=SYSTEM,
+            )
+        except LLMError:
+            return False  # unread: the driver reads it as an answer instead
+        return any(_yes(event) for event in produced)
+
+
+def _yes(event: Any) -> bool:
+    return (
+        isinstance(event, ToolCall)
+        and event.tool == "verdict"
+        and event.arguments.get("answer") == "yes"
+    )