fix(com): hatch islands on a live seat — typed edges become temporary entities

hatch_add_boundary was refused on COM (hatch_edge_paths), so a transverse
section of any hollow part — a bushing, a flange bore — could not be drawn in
AutoCAD at all: draw_prims asked the capability map and refused up front.

ActiveX takes a loop as whole objects, which is not the same as "cannot take a
typed edge": each edge now becomes a real temporary LINE, true ARC or ELLIPSE
in the hatch's own space, appended with AppendInnerLoop, evaluated and
deleted. A loop that is only chained lines becomes one closed polyline — one
COM call instead of 180 for a flattened bore. The edge list is validated in
full first with the headless engine's messages; a loop AutoCAD refuses is
taken back out with its temporaries.

Measured on AutoCAD 2026 (25.1s), in scratch documents closed unsaved:
- a two-arc island leaves exactly 10000 - 100*pi (9685.8407) of a 100 x 100 hatch;
- the OD40/ID20 sleeve's transverse section B-B, drawn through the view engine
  and draw_prims, hatches 942.2864 mm2 — the engine's declared 180-gon;
- an open chain is refused (E_FAIL) and the entity count is unchanged.

hatch_edge_paths is now supported on both engines.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FKFStjEFzpGyLq5bMpWxTd

README.md

@@ -27,7 +27,7 @@ Live through COM on Windows, or headless through ezdxf anywhere — one typed co
 
 </div>
 
-> **v1.5 release snapshot:** 229 tools · 8 resources · 5 prompt templates · 3995 collected tests.
+> **v1.5 release snapshot:** 229 tools · 8 resources · 5 prompt templates · 4005 collected tests.
 > 229 is the **registered** count; a default install advertises 224 over `tools/list`,
 > because `ENABLE_3D` is unset. `system_about` is the runtime authority.