feat(image): show the file path for an unresolved raster reference

An IMAGE whose file can't be opened (a URL, or a missing/renamed file) now
draws its clip/frame outline plus the saved path as centred text in the
image colour — AutoCAD's broken-reference placeholder — instead of an empty
frame. OCS never fetches remote paths. Bumps acadrust so the entity's path
is populated from its ImageDefinition.

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

Cargo.lock

@@ -73,7 +73,7 @@ checksum = "366ffbaa4442f4684d91e2cd7c5ea7c4ed8add41959a31447066e279e432b618"
 [[package]]
 name = "acadrust"
 version = "0.4.0"
-source = "git+https://github.com/OpenAEC-Foundation/acadifc?branch=main#27b0f1c0d0e9aed4ba6171e625b588dbc1076d5c"
+source = "git+https://github.com/OpenAEC-Foundation/acadifc?branch=main#70d57937c310c1814d624a58e17cf69ab33ba191"
 dependencies = [
  "ahash 0.8.12",
  "anyhow",