v0.4.21

Patch — the defect sweep (six measured defects from the dream session, root-caused and pinned).

• D1 — the marker could be stamped with a literal placeholder and silently ignored.
  Two dreams ran --stamp-marker HEAD with the literal arg; the stamp wrote the string
  "HEAD" verbatim (no validation), and the next read's _valid_sha guard silently
  cleared it → the first-consolidation fallback mis-scoped the whole pass. The stamp
  now RESOLVES its argument (rev-parse --verify <arg>^{commit} — bare rev-parse
  echoes any 40-hex without an object-DB lookup, the dead-SHA door), stamps the honest
  commit: "" + timestamp on a no-git/unborn-HEAD store (a refusal would exit-5 every
  no-git dream — the persist gate is timestamp-only), and REFUSES only unresolvable
  args in commit-ful repos (the state file stays byte-identical). The read now WARNS
  when it silently clears a non-empty invalid commit.
• D2 — the demotion verdict could contradict the scripted block. The validator now
  flags a verdict whose probative-count phrase contradicts windows_observed, and the
  SKILL binds the verdict's numbers to the block's own fields.
• D3 — the SKILL command template glued an argument into the quoted script path
  (copying it verbatim failed). Fixed + a smoke pin that no command line glues an arg
  inside the quotes.
• D5 — the distill scan's counts lived only in capped list lengths. The scanned
  block now carries the TRUE filtered pre-cap n_recurring/n_chains; the injection
  and the report's scale line use them (the capped lengths stay the output cap), the
  validator's "impossible count" backstop is dropped (the count is script-truth), and
  the SKILL names the exact fields to read — the class where the record's numbers and
  the model's verdict contradicted each other is closed.
• D6 — the suite's exact-count pin. An orphaned section (the double print/exit
  class) can never print green again: the final count is pinned exactly.

D4 (beat reuse) is a documented authorship ceiling, no code. Design-of-record:
docs/defect-sweep-v0421.spec.md (advisor + review-to-zero, amend-1/2/3 — the final
sweep's R1–R5 closed: the doc-wide quote-close pin, the mandate-format verdict
digits, the reconcile_marker gate, the resolution cwd + 40-hex belt, the dual-count
over-cap fixture). Backward-compatible → patch. Suite 1739 · browser 1105 ·
sim / manifests / mypy green.