feat: zipped packages, target set, checklists, audit fixes and a stress test

Features for the next six months (accessible HTML export, paperpack and
Lode on packages, the personal bundle):

- Zipped packages: the oracle writes and reads `.sct.zip` archives under
  the rules of spec/12 §12.2; validate.py and load.py accept them; a
  byte-identical zip of the tiny package joins the fixtures, and two
  broken archives (traversal, symbolic link) join fixtures/invalid.
- The target set of targeted F3 (spec/08 §8.10) is computed by the
  oracle and pinned by vectors/targets.jsonl under each digit rule; the
  rule now covers cells as well as sentences and the leaves of anchored
  containers, and defines a node's section.
- scienting-checklist/1 (provisional): a conformance check of an export,
  covered by a receipt as ["checklist", id, hash] (spec/08 §8.11), with a
  WCAG 2.1 AA fixture and its receipt.
- QA reports are signed like receipts (spec/08 §8.9).
- A `description` annotation body with role alt or long, so an
  accessible export can find a confirmed figure description; the layer
  fixture carries one, and the store's body-kind constraint allows it.
- scienting-spot-check/1, the seed payload, is registered with a schema.
- exercise, submission and grade are provisional until a course has
  used them.

Audit fixes, each with a vector or a broken package where one was
missing:

- Folder packages: symbolic links are refused on validate and load,
  manifest paths must not collide under case folding, listed files are
  matched by exact name, files are hashed in chunks under a size limit.
- Files are compared byte for byte, so CR LF, a byte order mark, NaN,
  a lone surrogate or invalid UTF-8 is refused instead of translated;
  integers beyond 2^53 are read as doubles, as canonical JSON writes them.
- Receipts: signature.key must equal by and the key must be valid when
  signed; a qa receipt's nodes must be the sample at the original's
  hashes, its scope must name qa.of, its errors must be sampled nodes;
  statuses are computed once, iteratively, so chains of spot-checks
  hundreds deep settle; Base64 and manifest shape errors become refusals
  instead of tracebacks; counts and the fidelity of roster-less packages
  are recomputed.
- The gate enforces rule 11 of spec/11 §11.4: changed nodes are
  validated against the node schema and the references between nodes
  are checked, so a set to a bad value, an insert with unknown
  properties or a delete of a referenced header cell is refused; a
  relabel to null drops the label; a reclassify drops foreign
  attributes; a split strips whitespace across runs; ids.jsonl order
  follows spec/04 §4.4 in every state; a move after itself is refused.
- Anchors: the relabel rule requires that nothing else changed below the
  node; an alias chain ending in a deletion no longer crashes resolve.
- Notation: a script after an empty group applies to the previous atom
  ({}^{14}C); letters are defined by Unicode block in spec/05 §5.4 and
  the oracle; \left) is complex.
- Page fingerprints delete whitespace before folding, so "10 -20" and
  "10-20" fold alike (spec/07 §7.1).
- Grades are summed with exact decimals; the reviewer error bound is
  computed with integer arithmetic.
- receipts and revocations are keyed by (doc_key, id) in SQL, since one
  revocation may be carried by several packages.

Checking:

- tools/stress.py: seeded randomized property tests over canonical JSON,
  normalization, notation, random correction walks, anchor resolution,
  Merkle roots, spot-check samples, error bounds, fingerprints, mutated
  archives and packages, rights and spot-check chains; CI runs it.
- check.py verifies every count and version the prose states against
  the repository, the zipped fixture and crafted archives, the checklist
  coverage, and nine more broken packages.
- CONTRIBUTING.md gains a release checklist.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

tools/validate.py

@@ -4,7 +4,9 @@
 Non-normative tooling.
 Usage: python3 tools/validate.py PACKAGE [PACKAGE ...]
        python3 tools/validate.py --correction PROPOSALS PACKAGE
-A package is checked as spec/22 §22.2 describes, and each failure printed as `package: where: rule: message`.
+A package is a folder, or a zipped package (`.sct.zip`), which is unpacked under the rules of spec/12 §12.2
+before it is checked. Each is checked as spec/22 §22.2 describes, and each failure printed as
+`package: where: rule: message`.
 With --correction, PROPOSALS is a JSON file holding one proposed correction, or a JSON Lines file of several
 applied in order. Each runs through the gate (spec/11 §11.4) against the package's current state, and the record
 it would append to corrections.jsonl is printed, until one is refused. Nothing is written.
@@ -15,6 +17,7 @@ import argparse
 import json
 import os
 import sys
+import tempfile
 
 ROOT = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
 sys.path.insert(0, ROOT)
@@ -33,19 +36,28 @@ def read_proposals(path):
         return [json.loads(ln) for ln in text.splitlines() if ln.strip()]
 
 
+def validate_one(path, store, limit):
+    """The validation report of a package folder or a zipped package."""
+    if package.is_zip(path):
+        return package.validate_zip(path, store, limit=limit)
+    return package.validate(path, store)
+
+
 def main():
     lines = __doc__.splitlines()
     ap = argparse.ArgumentParser(description=lines[0], epilog="\n".join(lines[5:]),
                                  formatter_class=argparse.RawDescriptionHelpFormatter)
     ap.add_argument("--correction", metavar="PROPOSALS",
                     help="a JSON or JSON Lines file of proposed corrections to run through the gate")
-    ap.add_argument("packages", nargs="+", metavar="PACKAGE", help="package folders")
+    ap.add_argument("--max-size", metavar="BYTES", type=int, default=package.ZIP_LIMIT,
+                    help="refuse a zipped package that expands past this many bytes (default %d)" % package.ZIP_LIMIT)
+    ap.add_argument("packages", nargs="+", metavar="PACKAGE", help="package folders or zipped packages")
     a = ap.parse_args()
     if a.correction and len(a.packages) != 1:
         ap.error("--correction checks proposals against exactly one package")
     store, bad = Store(os.path.join(ROOT, "schemas")), False
     for p in a.packages:
-        for e in package.validate(p, store).errors:
+        for e in validate_one(p, store, a.max_size).errors:
             print("%s: %s: %s: %s" % (p, e["where"], e["rule"], e["message"]), file=sys.stderr)
             bad = True
     if bad:
@@ -55,9 +67,12 @@ def main():
             print("%s: valid" % p)
         return 0
     pkg = a.packages[0]
-    state = package.read_state(pkg)
+    with tempfile.TemporaryDirectory() as tmp:
+        if package.is_zip(pkg):
+            pkg = package.read_zip(pkg, tmp, a.max_size)
+        state = package.read_state(pkg)
     if any(n.get("withheld") for n in state.nodes):
-        print("%s: doc.policy.withheld: a package that withholds its text takes no corrections" % pkg,
+        print("%s: doc.policy.withheld: a package that withholds its text takes no corrections" % a.packages[0],
               file=sys.stderr)
         return 1
     for i, proposal in enumerate(read_proposals(a.correction), 1):