add gpu ci

add gpu ci

fix(demo): add fallback to internal model when external model data is missingIf no valid model data is provided, the system now checks if an internal model
should be used. This enhances the robustness of the demo pipeline by providing
a default behavior when essential data is not available.

fix: object cluster algorithm

modify readme.md

Improve the model loading mechanism in magic_pdf by implementing a Singleton
pattern to reduce redundant model instantiation. Additionally, enhance the
command-line interface to support input from list files, allowing batch
processing of multiple PDF documents.

Add Chinese translations to the feature request issue template to enhance
accessibility for Chinese-speaking users and facilitate their contributionto the project.

Add Chinese translations to the bug report issue template to improve accessibility
for Chinese-speaking users and make it easier for them to contribute to the project.