`ProcessAttributeTypes.find_dependency()` failing to find simple types

[diana-crd]

Issue

When generating dataclasses from XML 1.0 schemas the method ProcessAttributeTypes.find_dependency() will seemingly fail to detect certain simple types when processing attributes, even when they are defined in the same .xsd file as other simple types that are correctly detected and kept in the final generated package.

How to reproduce

Versions: python==3.14.3, xsdata==26.2
Example 1:

• download the xsd files from https://github.com/ministero-salute/it-fse-catalogs/tree/main/schema;
• fix line 4 of POCD_MT000040UV02/CDA.xsd from <xs:include schemaLocation="./coreschemas/POCD_MT000040UV02.xsd"/> to <xs:include schemaLocation="./POCD_MT000040UV02.xsd"/>
• run xsdata:

xsdata generate POCD_MT000040UV02 -r --debug -ss clusters

Example 2:
Follow the instructions in [this repository](https://github.com/ipsosante/cda-bindings/tree/main) under ["Re-generate the bindings"](https://github.com/ipsosante/cda-bindings/tree/main#re-generating-the-bindings).

Both examples will result in a large amount of "Reset absent type" warnings from ProcessAttributeTypes.process_dependency_type() (~740 on example 1, ~150 from example 2), with many attributes reset to generic string types and the correct simple types just deleted.
The weird thing is that this behaviour appears to be inconsistent: taking Example 1, xsdata will reset all attributes of type ParticipationType (defined [here](https://github.com/ministero-salute/it-fse-catalogs/blob/ec177adfdb61001c30193fd909b6129d5c3266f8/schema/POCD_MT000040UV02/voc.xsd#L3385)) but correctly process attributes of type AddressPartType (defined [here](https://github.com/ministero-salute/it-fse-catalogs/blob/ec177adfdb61001c30193fd909b6129d5c3266f8/schema/POCD_MT000040UV02/voc.xsd#L2051)), despite both of them being defined in completely analogous ways and in the same file.
I'm attaching the debug output from example 1 in case it is of any help.

debuglog.txt