docs(measure): K3 unit worksheet delivered for operator, no code changed

Order 20260907T141419Z-2723316647-from-.claude: a 12-document, three-question
worksheet so the operator can answer the unit-of-knowledge question
docs/2026-09-07-k3-arm-e.md left open before any new arm is attempted. The
worksheet itself (concept splits per arm, extracted document structure,
blank checkboxes) is local-only and gitignored because it quotes corpus
content; this commit adds only the method record, which names no corpus
path or document title.

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

docs/2026-09-07-k3-enhetsark-metode.md

@@ -0,0 +1,90 @@
+# K3 unit worksheet, 2026-09-07
+
+Order `20260907T141419Z-2723316647-from-.claude`. Pure reading and
+generation: no production code, no threshold, no rating performed by this
+session. The worksheet itself is local-only and gitignored, because it
+quotes corpus document titles, extracted text, and concept splits, and this
+repo's public convention (`CLAUDE.md`) never tracks K2 corpus content or
+paths. This file states what the worksheet is and how it was built, without
+any of that content.
+
+## Why it exists
+
+`docs/2026-09-07-k3-arm-e.md` § Verdict left the K3 result conditional on a
+question no method text resolves: what counts as **one unit of knowledge** in
+this corpus -- a top-level chapter, a numbered subsection, or something else
+-- and whether a table is a unit on its own or only together with the prose
+that introduces it. The question surfaced twice on identical material: once
+under Arm D (two blind raters split on the same document), once under Arm E
+(the same document, same split, changed reasoning). It is prior to any
+threshold: a threshold on an undecided unit measures the rater, not the arm.
+
+The operator asked for a concrete artifact rather than an abstract question.
+This worksheet is that artifact: one worked example per sample document, with
+the operator's answer left blank, that becomes the reference the next K3
+round is measured against.
+
+## What the worksheet contains
+
+One section per document in the K3 sample (n = 12, the same draw every K3
+round has used), in canonical position order 0-11:
+
+1. **The concept split under three arms** -- Arm B (shipping default), Arm D
+   (`--outline-run 3`), Arm E (`--outline-run 3 --table-grid`) -- as an
+   indented list of concept title and character length per arm, capped at 25
+   lines with a `... (+N)` suffix when a document has more.
+2. **The document's own heading structure**, independent of any arm: every
+   ATX (`#`) and dotted-numbered heading the shipped grammar recognises, plus
+   contiguous table spans (a maximal run of pipe-delimited rows and grid rule
+   lines merged into ONE span, rather than fragmented the way the shipping
+   per-row candidate rule reads them) -- capped at 30 lines.
+3. **Three checkbox questions per document** -- what a unit is here, what a
+   table is here, which arm is closest today -- plus one free-text line, all
+   left blank for the operator.
+4. **A closing summary table**, 12 rows by 3 answer columns, that the
+   operator fills in. That filled table is the deliverable: the next K3
+   round measures against it, stated as such at the top of the worksheet.
+
+## How it was built
+
+Reading and generation only, run in the foreground this session, nothing
+written under `src/` or `tools/`:
+
+- The sample draw was reproduced via the shipped `draw_sample` function in
+  `tools/okf_outline_measure.py` (hex SHA-256 of the NFC-normalised filename,
+  stratified 8 pdf / 3 docx / 1 xlsx) against the corpus directory, **12/12**
+  matching the order published in `docs/2026-09-07-k3-arm-e.md` § Appendix.
+- Concept splits per arm were read from the archived plan JSON files for
+  this K3 round -- Arm B from the archived baseline plans, Arm D from the
+  archived Arm D plans, Arm E from the Arm E round's own plans -- matched to
+  each sample document via each archive's own `_index.txt` (position, exit
+  code, filename), not by re-deriving a path prefix.
+- The document's own heading structure and table spans were read with the
+  shipped `_ATX`, `_NUMBERED`, `_TABLE_ROW` and `_GRID_RULE` patterns from
+  `llm_ingestion_okf.propose`, imported rather than re-implemented, for the
+  same reason the reach instruments import them: a worksheet carrying its
+  own copy of the grammar would describe a second definition that can drift
+  from the shipped one without anything going red.
+
+## Verification
+
+- **Sample draw:** 12/12 documents match the published Arm E appendix order.
+- **Entry counts per arm, all 12 positions:** cross-checked against the
+  entries column of `docs/2026-09-07-k3-arm-e.md` § Appendix (Arm B / Arm D /
+  Arm E). All 36 figures (12 documents x 3 arms) matched exactly, including
+  the four documents where Arm B wrote no plan at all ("1 concept").
+- **Tracked-file content boundary:** this file was checked for the corpus
+  root directory name and any absolute filesystem path -> zero occurrences.
+  It names no document title, no corpus path, and no extracted text.
+- **Worksheet content boundary:** the local-only worksheet was checked for
+  absolute paths and the corpus root directory name -> zero occurrences; it
+  names document titles, which is expected and permitted in a local-only
+  file, but carries no filesystem path into the corpus.
+
+## What this is not
+
+No arm is built, changed, or shipped by this worksheet. No threshold is set.
+No rating is entered by this session -- every checkbox and free-text line in
+the worksheet is blank. The worksheet's own notes quote three findings
+already published in `docs/2026-09-07-k3-arm-e.md` (positions 5, 10, 11) as
+context for the operator's judgement; they are not new findings.