v0.3.9

Added

• Repeated recesses are dimensioned as one pattern, not N competing callouts
  (#841): identical blind pockets and identical through-slots now collapse to a single
  grouped 5× 7.9 × 13.6 × 19 DEEP / 4× SLOT 8 × 30 leader plus (n-1)× pitch
  dim(s). Previously each member competed for its own size dims and some silently
  dropped for want of strip room — five declared slots rendered only three length dims.
  Both new kinds (PocketPatternFeature, SlotPatternFeature) round-trip every
  surface: declare (sheet.pocket_pattern(...) / sheet.slot_pattern(...)),
  recognition from a real solid (coplanar, same-facing members only), the emitted
  Sheet script, and the editable surface (dwg.callout(feature) + finalize()).
• Sheet.section() and Sheet.detail() — ask for the view you need (#841/#847):
  a section A–A auto-fires only for a Z-axis hole with a counterbore, spotface, or
  blind bottom, so a blind pocket's floor and depth stayed hidden-line-only with no
  supported way to request a cut. sheet.section(feature) / section(at=y) /
  bare section() force one (the cut plane is validated to lie strictly inside the
  part), and sheet.detail() exposes the existing detail_view=True opt-in as a
  chainable verb.
• External threads are a first-class declared aspect (#859): the turned analog of
  the #764 internal thread — sheet.step(shaft).thread("M3x0.5"),
  sheet.diameter(...).thread(...), and sheet.boss(...).thread(...) append the
  spec to the ⌀ callout (ø3 M3x0.5) instead of needing a free-text .note(). It
  composes with .finish() for Ra-on-thread, keys the callout bucket on (⌀, thread)
  so a threaded and a plain ø6 stay distinct, and now round-trips through the Sheet
  emitter — including pattern-member holes, closing the symmetric latent #764 gap.
  Declaration-only: a plain cylinder is geometrically indistinguishable from a
  threaded one, so there is no recogniser. (Known limitation: the incremental
  callout/finalize(only=…) paths still dedup thread-blind — #863.)
• Blind obround pocket recognition, including imported STEP (#837): the blind
  counterpart of the #816 through-slot work. A stubby floored obround has side walls
  too short to pair, so it is recovered from its semicircular end caps — clustering
  faces by axis proximity so the quarter-cylinder split a STEP importer commonly
  produces recognises as well as build123d's half-cylinder. A sealed internal void
  (capped at both ends) is correctly not a pocket. A real tuner-jig STEP with five
  blind pockets ships as a fixture.
• sheet.slot(...).note(...) / sheet.pocket(...).note(...) (#841/#845): the
  slot/pocket handle now anchors a note to its own feature, with no ref= needed
  (an explicit ref still forwards, as before).

Changed

• An anchored note, GD&T frame, or finish relaxes its side instead of silently
  vanishing (#841/#855): an annotation declared with an explicit view=/side=
  used to drop with only a warning when that strip was full, while the export still
  reported success. The requested side is now a preference — when the strip has no
  room the placer tries the opposite side, then the two perpendicular sides, taking
  the first with room (via the same bounds and title-block checks, so it never
  overshoots). A relaxed placement records an INFO gdt_side_relaxed issue naming
  requested versus actual. Only when no strip fits does it drop.

Internal

• The state-bus endgame is closed to its permanent seam (#830/#840): the
  solve trace is filled into BuildState at the one construction site, the redundant
  part-model re-attach is gone, and the detail view is now transactional — geometry
  is projected at the detail scale and committed only if dimensions land, so
  _drop_view_coordinates has zero engine callers. With those removed, the #817
  decision-D method-call exemption narrows from a blanket pass to a named
  _LAYOUT_SEAM allowlist (_add_view, _set_view_coordinates), accepted as the
  permanent interactive-layout seam; every other private-method call on the drawing
  is now flagged.
• A draftwright logo set (#843) — drafting-idiom mark, all text outlined so the
  SVGs render font-independently; the README now leads with the lockup.
• A worked multi-feature object-reference example (#853) in
  docs/multi-feature-object-reference-workflow.md.