SUBIM ResourceLoader Core baseline note

Main program baseline: SUBIM Workbench V1.2.66 encryption-ready package.
This V1.2.67 package keeps the V1.2.66 official-encryption-compatible Sketchup.require loading structure.
Resource loading logic is aligned to WUZUO Design Materials Library V1.0.66 stable baseline.

Rules preserved:
1. PB assembly detection must read internal SKP PB fields.
2. Do not classify PB assembly by file name, WZ/ID code, category name, or furniture keywords.
3. PB profile keeps its original route.
4. Normal models continue normal loading if no PB fields are detected.
5. rubyzip remains a normal vendor fallback and must not be encrypted together with business Ruby files.
