Backdrop generation

[nighca]

close #2591, #2659, #2682.

[Copilot]

Pull request overview

This pull request implements backdrop generation functionality for the SPX GUI, closing issues #2591, #2659, and #2682. The implementation refactors the backdrop generation flow to match the sprite generation pattern, introducing a multi-step generation process with image selection and preview capabilities.

Key changes include:

• Refactored backdrop generation model to support batch image generation (4 images at once) and user selection
• Created reusable UI components (ImageSelector, ImagePreview, LayoutWithPreview) shared between sprite and backdrop generation
• Integrated backdrop generation into the asset library modal with a unified user experience

Reviewed changes

Copilot reviewed 22 out of 22 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
spx-gui/src/models/gen/backdrop-gen.ts	Refactored to use Task-based batch image generation and added image selection state management
spx-gui/src/models/gen/backdrop-gen.test.ts	Updated tests to reflect new batch generation API
spx-gui/src/models/gen/sprite-gen.ts	Added name getter/setter for consistency with backdrop generation
spx-gui/src/apis/aigc.ts	Removed deprecated genBackdropImage and untilTaskCompleted helper functions
spx-gui/src/components/asset/library/AssetLibraryModal.vue	Integrated backdrop generation with finish handling and modal size adjustments
spx-gui/src/components/asset/gen/backdrop/*	Complete rewrite of backdrop generation UI components with image selection and preview
spx-gui/src/components/asset/gen/sprite/*	Refactored to use shared ImageSelector and LayoutWithPreview components
spx-gui/src/components/asset/gen/common/*	Created reusable components for image selection, preview, and responsive layouts
spx-gui/src/components/ui/modal/UIFormModal.vue	Added flex layout styling for better content positioning
spx-gui/src/components/asset/index.ts	Removed unused useBackdropGenModal export and BackdropGenModal import

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[Copilot]

The disabled prop is passed to BackdropSettingInput in line 38 but is not defined in the component's props interface. This prop is not being used within the component and should either be removed from the parent call or added to the props definition.

Suggested change

	<BackdropSettingInput :gen="gen" :disabled="handleSubmit.isLoading.value" />
	<BackdropSettingInput :gen="gen" />