feat(cad): integrate standard codec coverage

Render, edit, query, select, and explode newly decoded standard entity variants. Pin acadifc de8d6b5 and preserve None color semantics.

src/app/helpers.rs

@@ -383,6 +383,7 @@ pub(super) fn entity_type_key(entity: &acadrust::EntityType) -> String {
         Light(_) => "light",
         SectionSymbol(_) => "sectionsymbol",
         ViewBorder(_) => "viewborder",
+        Extended(entity) => return entity.class_name().to_ascii_lowercase(),
         Seqend(_) => "seqend",
         Unknown(_) => "unknown",
     }