test(gates): retire the K2 track; re-measure the retrieval gate's premises for BM25

Operator decision 2026-09-21: the test track built on material tied to the
operator's employer (K2) is retired -- not re-measured, not frozen. Public
tests and gates run on invented material.

Retrieval gate:
- The four FUSION_PREMISE xfails are gone and pass through their INPUTS: the
  synthetic MISS, LOOKUP and QUOTA bundles were re-measured for BM25 (the
  miss fasit no longer shares the rare word `maa`; lookup and quota decoys
  carry the question's words so each partition and the quota decide their
  own fixture). SPECS_SHA256 moved with them. Rows 2 and 3 green again.
- Row 7's mutants M04, M06, M07, M08, M10 now patch `bm25`, the code the
  default runs. Three survive with 0 ranks moved (passage body, title
  weight, bm25.RRF_K), each with its mechanism printed. M07 was not forced:
  every synthetic body carries its title as a heading.
- Row 9 (K2) removed; row 8 requires `wiki-20` alone, the `r761` and
  `vegnormal` adapters are gone. Chose the broad reading of "K2" because the
  operator decision defines it as employer-tied material and the order's
  grep includes `vegnormal`.

Also removed: tests/test_default_bundle_pin.py, the K2 arms of
test_okf_consume, the four real-arm tests of test_quality, the R761 soft
hyphen test, the N101/N200 delivery tests and okf_accounting_gate's default
real corpus (and H5's guard, which only existed for those defaults). Two
fixtures carrying road-standard identifiers are rewritten with invented ones.

Gate after: 1 10/10, 2 7/7, 3 5/5, 4 6/6, 5 0/1, 6 10/10, 7 11/14,
8 NOT RUN -> GATE RED: rows 5, 7, 8. Suite 2423 passed, 1 skipped,
0 xfailed.

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

tools/okf_accounting_gate.py

@@ -102,8 +102,9 @@ STS_TWIN = FIXTURES / "witness" / "prosess-84-sts.twin.json"
 PDF_FIXTURE = CORPUS / "prosess-84-tabell.pdf"
 README = REPO / "README.md"
 
-R761_DEFAULT = Path.home() / "repos" / "vegnormal-okf" / "data" / "raw" / "860019"
-N200_DEFAULT = R761_DEFAULT.parent / "N200-2024-860015.json"
+#: No DEFAULT real corpus since 2026-09-21: the two this row was built on are
+#: material tied to the operator's employer, and that test track is retired.
+#: Row 6 measures a real corpus only when one is named on the command line.
 R761_ZIP = "14ce59dc-2150-480b-b661-6ea605fe3b24.zip"
 R761_JSON = "R761-2025-860019.json"
 R761_PDF = "R761-prosesskoden-2025.pdf"
@@ -1408,14 +1409,14 @@ def main(argv: list[str] | None = None) -> int:
     parser.add_argument(
         "--r761",
         type=Path,
-        default=R761_DEFAULT,
-        help="directory holding the R761 zip, JSON and PDF (read only)",
+        default=None,
+        help="directory holding the R761 zip, JSON and PDF (read only; no default)",
     )
     parser.add_argument(
         "--n200",
         type=Path,
-        default=N200_DEFAULT,
-        help="the N200 JSON delivery, the second real corpus (read only)",
+        default=None,
+        help="the N200 JSON delivery, the second real corpus (read only; no default)",
     )
     parser.add_argument(
         "--consume", action="store_true", help="also run row 7 (diagnostic, never fails)"
@@ -1447,23 +1448,10 @@ def main(argv: list[str] | None = None) -> int:
         print(json.dumps(payload, indent=2, ensure_ascii=False))
     else:
         print(render(rows), end="")
-    if any(r.fails for r in rows):
-        return 1
-    # A row skipped while its source is on this machine did not run, and a
-    # zero here would report that as a pass. Measured against the DEFAULT
-    # sources, never against the arguments: a row is SKIPPED exactly when the
-    # corpora the arguments name are absent, so asking the arguments made this
-    # branch unreachable (H5). Pointing `--r761` at nothing on a machine that
-    # holds R761 is the case it exists for.
-    machine = real_corpora(R761_DEFAULT, N200_DEFAULT)
-    for row in rows:
-        if row.status == SKIPPED and any(c.available for c in machine):
-            print(
-                f"okf-accounting-gate: row {row.number} was skipped while its source exists",
-                file=sys.stderr,
-            )
-            return 1
-    return 0
+    # H5's guard -- a row skipped while a DEFAULT source sat on this machine
+    # exits 1 -- went with the defaults on 2026-09-21: with no default source
+    # the gate knows of no corpus it could have been pointed away from.
+    return 1 if any(r.fails for r in rows) else 0
 
 
 if __name__ == "__main__":