feat: dark mode for collection and nft details pages

[patricio0312rev]

[general] dark mode: [collections] collection detail dark mode, [nfts] activity table dark mode, [nfts] header dark mode, [general] dark mode image placeholder & [general] image loading state swaps colors

Summary

• Skeleton loader in collection page has been fixed. The purple color appearing when finishing loading has been removed.
• Placeholder for NFT's with no image is correctly appearing.
• New className prop for Point component.
• Collection and NFT details pages now fully support dark mode.

Screen.Recording.2023-10-23.at.08.31.47.mov

Checklist

• I checked my UI changes against the design and there are no notable differences
• I checked my UI changes for any responsiveness issues
• I checked my (code) changes for obvious issues, debug statements and commented code
• I opened a corresponding card on Clickup for any remaining TODOs in my code
• I added a short description on how to test this PR (if necessary)
• I added a storybook entry for the component that was added (if necessary)
• Documentation (if necessary)
• Tests (if necessary)
• Ready to be merged