feat(p19): a direction must NAME the requirement that binds it, and have READ it

Two paid rounds scored 0 of 26 fasit concepts opened -- the same number twice.
P18 closed the navigation side (a listing is a window, an invented path is
refused by name) and it did not move, which makes it a ROLE question: nothing
in the loop ever asked the model to say what requirement binds the direction it
committed to, so opening one was never on the critical path to an answer.

A PREMISE OF THE ORDER WAS FELLED BEFORE ANYTHING WAS BUILT ON IT. A1 places
the demand in _INSTRUCTIONS[HYPOTHESISER_ROLE] alone. Measured: the stress
command sends --mandate and NOT --explore, the two are refused together by
name, and none of the nine round-1/2 outboxes holds a {run_id}-exploration.json
-- the hypothesiser never runs in a stress round, so A3 would have been
unreachable in exactly the paid runs this order commissions.

A2's own sentence resolves it: the refusal goes to the model "som en tur den
kan rette (samme mekanisme som quick_validate's nekt), ikke som en raise" --
and quick_validate IS a tool. declare_requirement therefore lives in
navigator_tools, held by BOTH roles that navigate (the exploration, and since
S2c the debate). It EXISTS only when the caller offers both sinks, which keeps
every pre-P19 call site byte-identical; one sink without the other is refused
at construction. 'opened' is the SAME list ExplorationToolRecorder fills, so
the refusal reads the run's own read trace.

The marked hypothesis carries 'requirement' as a REQUIRED key: omitted is a
hard error, explicit null is legal and needs 'why_none', a half-named one is
refused. A minted approach carries it; a seed never acquires one. The proposer
prompt names it only when the field exists, and the judge counts a hit against
THIS approach's fasit concepts, never against the base.

Load-bearing measured (12 arms), four mutations all red against the whole
suite, green control 1711/5 and demo-transcript.stdout byte-unchanged.
A-iii's predicted signature was FALSIFIED: the golden stays green because the
demo runs without a mandate, so _build_messages' approach branch is never
taken there. A-iv was GREEN first -- the repo's vacuous-gate class, 24th time:
the arm drove _attributable while the hit is computed at the call site.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/portfolio_optimiser/outbox.py

@@ -194,8 +194,10 @@ def write_debate_tools(
     run_id: str,
     *,
     tool_calls: Sequence[Mapping[str, Any]],
+    requirements: Sequence[Mapping[str, Any]] = (),
 ) -> Path:
-    """Write ``{run_id}-debate.json`` — WHICH documents the debate opened, in call order (S2c).
+    """Write ``{run_id}-debate.json`` — WHICH documents the debate opened, in call order (S2c), and
+    WHICH requirement it declared as binding (P19 DEL A).
 
     The sibling of ``write_exploration`` one phase over. Since S2c the debate navigates the
     knowledge base instead of being handed it whole, so "what did this run actually read" is a
@@ -213,7 +215,16 @@ def write_debate_tools(
     directory.mkdir(parents=True, exist_ok=True)
     path = directory / f"{run_id}-debate.json"
     path.write_text(
-        _dump({"run_id": run_id, "tool_calls": [dict(call) for call in tool_calls]}),
+        _dump(
+            {
+                "run_id": run_id,
+                "tool_calls": [dict(call) for call in tool_calls],
+                # DEFAULTS to empty for the same reason ``Bundle.skipped`` does: "this debate
+                # declared nothing" is an honest positive statement, and it is the one every run
+                # written before today makes.
+                "requirements": [dict(r) for r in requirements],
+            }
+        ),
         encoding="utf-8",
     )
     return path