Add OverrideInitData adapt_structure for GPU compatibility

- Analyzed isbits requirements and OverrideInitData field types
- Found that metadata field is primary GPU compatibility issue
- Added adapt_structure for OverrideInitData that:
  * Adapts initializeprob field to target backend
  * Sets metadata to nothing for GPU compatibility
  * Preserves all other functional fields
- Testing shows successful DAE solving with constraint satisfaction
- Neither approach makes OverrideInitData fully isbits due to field type limitations
- Current implementation provides sufficient GPU compatibility

🤖 Generated with [Claude Code](https://claude.ai/code)

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

Author: claude

src/dae_adapt.jl

@@ -12,3 +12,15 @@ function adapt_structure(to, f::SciMLBase.ODEFunction{iip}) where {iip}
         initialization_data = f.initialization_data
     )
 end
+
+# Adapt OverrideInitData for GPU compatibility
+function adapt_structure(to, f::SciMLBase.OverrideInitData)
+    SciMLBase.OverrideInitData(
+        adapt(to, f.initializeprob),  # Also adapt initializeprob
+        f.update_initializeprob!,
+        f.initializeprobmap,
+        f.initializeprobpmap,
+        nothing,  # Set metadata to nothing for GPU compatibility
+        f.is_update_oop
+    )
+end