[Docs] Add Z-Image docs (#12775)
* initial
* toctree
* fix
* apply review and fix
* Update docs/source/en/api/pipelines/z_image.md
Co-authored-by: Steven Liu <59462357+stevhliu@users.noreply.github.com>
* Update docs/source/en/api/pipelines/z_image.md
Co-authored-by: Steven Liu <59462357+stevhliu@users.noreply.github.com>
* Update docs/source/en/api/pipelines/z_image.md
Co-authored-by: Steven Liu <59462357+stevhliu@users.noreply.github.com>
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Co-authored-by: Steven Liu <59462357+stevhliu@users.noreply.github.com>