feat(header):Add header component and cleanup

[nickhowell6425]

• Add optional header component with flexible content sections

• Move logo to dedicated assets directory for better organization

• Fix types import warning for better type safety

• Add Storybook documentation and examples

PR Checklist

Please check if your PR fulfills the following requirements:

• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[X] Bugfix
[X] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Documentation content changes
[ ] Other... Please describe:

What is the current behavior?

Issue Number: N/A

What is the new behavior?

Added a new optional Header component to the chat companion.

Does this PR introduce a breaking change?

[ ] Yes
[X] No

Other information

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[steppy452]

left a few comments around flexibility of the AppBar content

[nickhowell6425]

@steppy452 Updated, thanks!

[steppy452]

it's beautiful 🎉