chore(deps): bump acadrust 7e20fd1 — DXF dangling-ref cleanup

DWG→DXF conversion now drops references to objects that have no DXF form
(unsupported AEC/application objects dropped on conversion), so the output
opens clean instead of auditing 619 dangling handle references.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Cargo.lock

@@ -71,7 +71,7 @@ checksum = "366ffbaa4442f4684d91e2cd7c5ea7c4ed8add41959a31447066e279e432b618"
 [[package]]
 name = "acadrust"
 version = "0.4.0"
-source = "git+https://github.com/HakanSeven12/acadrust?branch=main#ffdd4944ece662fdd5a08ac8db6368955b368ad5"
+source = "git+https://github.com/HakanSeven12/acadrust?branch=main#7e20fd1968caaca32a3dc6e7c66c936782df590f"
 dependencies = [
  "ahash 0.8.12",
  "anyhow",
@@ -3160,7 +3160,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0b577e2d69827c4740cba2b52efaad1c4cc7c73042860b199710b3575c68438d"
 dependencies = [
  "bytecount",
- "memchr 1.0.2",
+ "memchr 2.8.2",
  "nom 8.0.0",
 ]