StepperButton & StepperCombo - build & document internal components

[thrbnhrtmnn]

Description / User Story

The StepperButton & StepperCombo currently exists in design and their tokens are also part of the NumberInput in code. With this task we want to implement both as internal components.

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Requirements

• StepperButton - rename tokens #770

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Acceptance Criteria

• StepperButton is a component in the code
• StepperCombo is a component in the code
• A page for the StepperButton exists in Storybook (similar to design template and other components)
• A page for the StepperCombo exists in Storybook (similar to design template and other components)
• Props used are similar to design (size-variant, layout, icons, disabled) and have been documented in the Props Excel.

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Background information

• Should it be placed under internal components? > yes
• Should it also be used in the Slider where we currently use Icon buttons? (may be already its own task) > Create a follow up task for this.