feat: Add isSliced option to the Name and Address component

[cpcramer]

What changed? Why? Tracking issue: https://github.com/coinbase/onchainkit/issues/732

Part	Description	Status
1	[Part 1] feat: Add isSliced option to the Name and Address component	In Progress
2	[Part 2] docs: Add isSliced option to the Name and Address component	In Progress

Add the isSliced option to the Name and Address component. This allows these components to render the full users address when set to false.

• Add unit tests for both true and false cases.
• Update the getName function to return null if the ENS Name is not found.

Notes to reviewers

How has it been tested?

Notes to reviewers

How has it been tested? Tested locally in docs.