Implement improved code examples

[BoppLi]

In cases that need functions in storybook examples, we should create a demo component file and reference the code like here:
packages/sit-onyx/src/components/examples/FormExample/FormExample.stories.ts

import FormExampleSourceCode from "./FormExample.vue?raw";
// ...
const meta: Meta<typeof FormExample> = {
  // ...
  parameters: {
    docs: {
      source: {
        code: FormExampleSourceCode.replace('from "../../.."', 'from "sit-onyx"'),
      },
    },
  },
};

List of examples we should change:

• https://storybook.onyx.schwarz/?path=/docs/feedback-dialog--docs -> modal
• https://storybook.onyx.schwarz/?path=/docs/form-select--docs
  • withCustomSearch
  • LazyLoading
  • WithSearch
  • ButtonLoading
• https://storybook.onyx.schwarz/?path=/docs/navigation-modules-colorschemedialog--docs

Acceptance criteria

• the abovementioned examples have demo vue files which are bound in storybook
• for those examples, the controls are deactivated (as changing the controls will not have any effect on the
  demo anymore)

[BoppLi]

Full example context