feat(settings): live COM smoke on AutoCAD 2026 builds the five .dwt twins and records the run

scripts/smoke_settings_com.py --build-dwt exited 0 on AutoCAD 2026 (25.1s),
2026-09-22: five templates/*.dwt written through drawing_template_save
(SaveAs code 66, each file opens with AC1032), page setup plotted and the
PDF's own /MediaBox read back as 420.158 x 297.039 mm, iso_a3_mech.dwt
reopened as source "bundled" with ISO-25 current, layer state / named view /
UCS / preferences / SummaryInfo / prompt line all through the COM engine.
The record is in CHANGELOG.md under Unreleased. The smoke keeps a ledger of
the documents it opens and closes them on the way out, so a failed run never
leaves scratch documents on the operator's seat. Two of its expectations
were corrected to the merged tree: mleaderstyle_create is implemented on COM
(spec: no `mleaderstyle` key), and plot_style_list marks catalogue rows with
`installed`. --interactive was not run unattended on the shared seat (an
unanswered GetPoint holds the command line); Task 23 measured the pick live.
*.dwt / *.dwg are binary in .gitattributes; AutoCAD's plot.log is ignored.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FKFStjEFzpGyLq5bMpWxTd

templates/README.md

@@ -26,7 +26,7 @@ listed by `drawing_template_list`. Start from one with
 - `<name>.dwt` — the live twin, used by `drawing_new(template=…)` on the COM
   backend. AutoCAD's DWT is a DWG container, which no headless library
   writes, so these are produced **on the live machine** by
-  `uv run --frozen python scripts/smoke_settings_com.py --build-dwt` (Task 24's
+  `uv run --frozen python scripts/smoke_settings_com.py --build-dwt` (Task 25's
   smoke): it opens each DXF over COM and calls `drawing_template_save(…dwt)`
   (`SaveAs(path, ac2018_Template)`), then the files are committed once. While
   a `.dwt` is missing, `resolve_template` falls back to the DXF and reports
@@ -43,3 +43,9 @@ to CRLF so a checkout on any platform equals a fresh build.
 Rebuild after changing anything the build depends on (layer sets, the title
 block, the dimension presets, the settings facade) and commit the result
 together with the change — the reproducibility test is the gate.
+
+The `.dwt` twins were built on 2026-09-22 on AutoCAD 2026 by
+`scripts/smoke_settings_com.py --build-dwt` — each DXF opened over COM and
+saved as a template (`AcSaveAsType` 66, `ac2018_Template`). Rebuild them the
+same way after changing a DXF; `scripts/build_templates.py --check` gates the
+DXF side only.