Fix: Move frontpage to top-level navigation for easier access

[khushishukla2813]

📝 Description

• Moved the frontpage (Intro to DUB) to the top-level navigation.
• This change eliminates the unnecessary nesting, making it easier to access the full documentation without multiple back clicks.
• Fixed navigation behavior that caused confusion, especially on mobile devices.

📱 Mobile Improvement

• Previously, navigation started at the second-level, making it cumbersome on mobile.
• Now, the homepage is directly accessible, eliminating the need to click the back button multiple times.

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🎨 Proposed New Design

I have also designed an improved version of the page with better navigation.
✅ If you like it, I would be happy to proceed with that design as a future enhancement.

📂 Files Changed:

• mkdocs.yml

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🔗 Reference Issue:

Closes #88

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[WebFreak001]

Suggested change

	- "Intro to DUB": index.md # Moved to top level
	- "Intro to DUB": index.md

putting in a comment will just confuse people reading the code in the future when they expect it to be top level and haven't seen it anywhere else

[WebFreak001]

perhaps this side panel should be removed (for the front page only)

do you think you can find it in the docs in https://squidfunk.github.io/mkdocs-material/ ?