chore(deps): bump acadrust to R2018 cross-version conformance fixes

Pins acadrust 0831995 (HakanSeven12/acadrust main): cross-version DWG
writer/reader conformance so R2004->R2018 saves open in AutoCAD for
LAYER, VPORT and ATTRIB objects (22/25 previously-discarded objects in
the Civil3D test file now open clean). MLEADER cross-version still WIP.

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#3dbae0556208221822257ead37a8d445dcc7d768"
+source = "git+https://github.com/HakanSeven12/acadrust?branch=main#0831995f4b219b8ff7e7b1b52bd147760880ff13"
 dependencies = [
  "ahash 0.8.12",
  "anyhow",
@@ -3884,6 +3884,7 @@ version = "0.1.0"
 dependencies = [
  "acadrust",
  "bincode",
+ "getrandom 0.2.17",
  "interprocess",
  "libloading",
  "memmap2",