This commit refactors the button component styles by introducing a new `kind` prop to replace the `filled` and `outlined` props. The `kind` prop takes values "filled", "outlined", or "plain". It also updates the usage of the button component in other components, using the new `kind` prop. Additionally, the button stories have been updated to remove redundancy and use the new `kind` prop.
Changes:
- Introduce `kind` prop in Button component
- Remove `filled` and `outlined` props
- Update button usage in BackForwardButtons and Breadcrumbs components
- Update Button.stories to use new `kind` prop
This commit improves the visualization of diffs in the CodeViewer and makes several adjustments to the interface, which enhances the user experience.
Changes:
- Add padding to code lines and update line colors for context, split, and diff classes.
- Modify background color values for addition and deletion markers.
- Add contrasting text color to addition inner diffs: white.
- Update lineClass assignment in DiffViewer.svelte to reflect new colors.
- Reorganize project overview page: move work-in-progress sidebar to the right.
- Rename class "work-in-progress-sidebar" to "side-panel" for clearer naming convention.
