TEST-26: a missing value in a check is a named FAIL, not a traceback

Checks and prints that indexed an empty list, exhausted next(), or formatted
None killed the rest of their file (FCST-06). Read them through the new
named_absence.py (nth/first/field/given/present) and conjoin a presence term.

- every site in the brief, plus the family the new scan and a sweep found
- test_named_absence.py: scans every test_*.py for unguarded filtered-list
  indexing, next() without a default and numeric formats on maybe-None
  names; proven to bite; prints what it cannot see, counted
- test_price.py 16a: the `_T17_CAPS is _T17_CAPS` tautology now grades the
  two assemble() calls' arguments
- test_control.py: coverage table re-measured on runs graded to the end

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BwRLw7eKYj2byVdwB6kbjU

goodwe_controller/test_arbitrage.py

@@ -79,6 +79,7 @@ import sys
 from datetime import datetime, timedelta, timezone
 
 from app import arbitrage as _arb
+from named_absence import first
 from app import main as _main
 from app import peakguard as _pg
 from app.arbiter import (
@@ -933,12 +934,12 @@ check("main.py passes the guard's OWN measured headroom at its one "
 # once in `__init__` and never refreshed would satisfy the pin above and would
 # size every trade from the guard decision of whatever cycle happened to run
 # last - which is the defect the hoist's own comment warns about, one level up.
-_s45_cycle = next(n for n in ast.walk(_S45_MAIN_TREE)
-                  if isinstance(n, (ast.FunctionDef, ast.AsyncFunctionDef))
-                  and n.name == "cycle"
-                  and any(isinstance(c, ast.Call)
-                          and ast.unparse(c.func).endswith("arbitrage.decide")
-                          for c in ast.walk(n)))
+_s45_cycle = first((n for n in ast.walk(_S45_MAIN_TREE)
+                    if isinstance(n, (ast.FunctionDef, ast.AsyncFunctionDef))
+                    and n.name == "cycle"
+                    and any(isinstance(c, ast.Call)
+                            and ast.unparse(c.func).endswith("arbitrage.decide")
+                            for c in ast.walk(n))), "no cycle() calling arbitrage.decide")
 check("...and the assignment is INSIDE the same `cycle()` that makes the call, "
       "so the headroom the trade is sized from is this cycle's guard decision "
       "and not one carried from an arbitrary earlier one",
@@ -1069,22 +1070,23 @@ def s45_loop(*, sized: bool, cap_w=S45_CAP_W, load_w=S45_LOAD_W,
             res = resolve(claims)
             target = res.target_w
             head_w = _pg.charge_headroom_w(pk) if sized else HEADROOM_CLEAR
-            rec.append(dict(
+            row = dict(
                 t_s=t, action=arb.action, power_w=arb.power_w,
                 reason=arb.reason, price=arb.price_now_eur_kwh,
                 spread=arb.spread_eur_kwh, winner=res.winner,
                 target_w=float(res.target_w), headroom_w=head_w,
                 engaged=bool(pk.engaged),
                 sized_from_meter=_arb.sized_from_meter(
-                    arb, head_w, winner=res.winner)))
+                    arb, head_w, winner=res.winner))
+            rec.append(row)
             if shadow:
                 # --- TRANSCRIBED 1/3: `_shadow_settle()`'s record, taken
                 #     BEFORE the re-seed destroys its evidence.
-                rec[-1]["would_w"] = float(res.target_w)
-                rec[-1]["row"] = _shadow.words(
+                row["would_w"] = float(res.target_w)
+                row["row"] = _shadow.words(
                     {"shadow_mode": "on"}, control_started=False,
                     would_w=float(res.target_w),
-                    sized_from_meter=rec[-1]["sized_from_meter"],
+                    sized_from_meter=row["sized_from_meter"],
                     reason=res.explain())
                 # --- TRANSCRIBED 2/3: `_write_unit()`'s substitution - the
                 #     plant below is driven from WIRE_W, not from the decision.