feat(frozen-bundles): the measurements read a pinned copy, not another repo's build dir

Measured 2026-09-17 17:43: vegnormal-okf rebuilt build/ferdig/r761-2025 while this
repository's v1 gate, the stress judge and four corpus tests pointed straight at it.
Rows 6-7 went IKKE MAALT and five tests fell, for a change no one here made. The failure
mode was never falsehood - the gate says IKKE MAALT and exits non-zero, never green - it
was instability: two projects shared a directory neither owns, so what this repository
MEASURES could move without a commit here.

A copy alone would push that directory one move away, so the copy comes with a pin.
frozen_bundles.json (tracked) carries path + sha256 + file count per base; the bundles
themselves are NEVER committed here. Three states, separated by construction: match ->
resolves; gone -> FrozenBundleMissing (an OSError, so the gate's existing except OSError
gives IKKE MAALT + exit 1 unchanged and the corpus tests SKIP, MAJOR-3's ceiling); drift
-> FrozenBundleDrift (a ValueError), loud, named, and never a skip. The two classes are
deliberately unrelated: a caller that catches "missing" to skip must not swallow "drift".

The NAME is hashed alongside the bytes, and the directory name carries the first 12 chars
of the digest so a stale copy is visible in ls. Renewal is a decision: new copy + new pin
in the SAME commit (README). --bundle-root / PORTFOLIO_VEGNORMAL_ROOT stays as the
operator's explicit, UNPINNED live mount.

Iron Law: the tests were written and run RED first (collection error, then two arms of my
own making). Load-bearing MEASURED, eight mutations all red against the WHOLE suite with a
green control of 1984 passed / 5 skipped / 5 xfailed and a strict node-id superset
(1977 -> 1994, 0 removed): M1 the pin is never verified (7) - M2 drift collapsed into
missing (5) - M3 the name is not hashed (40) - M4 the gate seam reverted to root/name (1) -
M5 the corpus helpers skip on drift too (4, one per file) - M6a the slash spelling back in
src (1) - M6b the quoted path segment back in a test (1) - M7 the directory name drops the
short digest (1, and 45 skipped, which proves absence is a SKIP and not a false green) -
M8 the explicit override ignored (3, two of them in test_stress_judge_loadbearing.py,
independent witnesses older than this work).

M2 FALSIFIED THE TEST FIRST: the four parametrised arms did not go red, they went to SKIP
(5 -> 9 skipped) and stayed green - pytest.skip inside a pytest.raises is not a failure.
The arm now catches pytest.skip.Exception explicitly and turns it into an AssertionError.

grep -rnE 'vegnormal-okf/build|["'"'"']vegnormal-okf["'"'"']' src tests contexts -> 0
(3 + 4 hits before; the three remaining prose mentions document history and are allowed).
Gate re-run against the frozen copy: identical to the live mount (rows 0/3 - 0/3 - 3/8 -
no report - 3/8 - IKKE MAALT - 1/20, exit 1).

Order 20260917T223645Z-1296211942-from-.claude.

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

README.md

@@ -1040,3 +1040,17 @@ uv sync
 uv run pytest
 uv run ruff check .
 ```
+
+### Frozen knowledge bases
+
+The measurements that read a delivered corpus (the v1 gate's rows 6–7, the stress judge, and four
+corpus tests) read a **frozen copy** under `~/corpora/po-frosne-bundles/<name>-<short sha256>/`,
+outside every repository, pinned by `src/portfolio_optimiser/frozen_bundles.json`. The bundles
+themselves are never committed here; only the pin is. A copy that no longer matches its pin fails
+loudly (`frosset bundle … avviker fra pin`), and a copy that is absent is `IKKE MÅLT`, never green.
+
+**Renewing a copy is a decision, not maintenance: a new copy and a new pin go in the SAME commit.**
+Re-copy the base, recompute with `portfolio_optimiser.frozen_bundles.digest_bundle`, rename the
+directory to carry the new short digest, and update `frozen_bundles.json` in that same change.
+`--bundle-root` (or `PORTFOLIO_VEGNORMAL_ROOT`) stays as an explicit, **unpinned** live mount — the
+way to look at a fresh corpus before deciding to refreeze.