feat: customizable homepage

[drodil]

Hey, I just made a Pull Request!

Allows customizing homepage components, their placement, size, and individual settings. For maximum size and settings, the existing home components should change to use createCustomizableCardExtension function. This disables the default Settings entity and replaces it with form using react-json-schema-form.

relates to #16535

:heavy_check_mark: Checklist

• [x] A changeset describing the change and affected packages. (more info)
• [x] Added or updated documentation
• [ ] Tests for new functionality and regression tests for bug fixes
• [x] Screenshots attached (for UI changes)
• [x] All your commits have a Signed-off-by line in the message. (more info)

[Nitinvonage]

@drodil sure, let me open a ticket for the same and explain the issue and possible implementation, though i would love to go with local storage way as I can see we are already storing @backstage/core:SignInPage:provider, sidebarPinState and other info in it. Deleting LS without a purpose would surely create some issue, but we can do some handling there.

lets start brainstorming there :)