fix: prevent onboarding tooltip from going off-screen

[Saylee12R]

Description

Fixed the onboarding tour tooltip positioning issue where the tooltip could move outside the viewport during step transitions, causing content to become partially or completely unreadable.

Changes Made

• Added viewport boundary checks for tooltip positioning.
• Prevented tooltips from rendering outside the visible screen area.
• Improved onboarding tour readability during step transitions.
• Ensured tooltip content remains accessible and visible throughout the onboarding flow.

Related Issue

Fixes #1521

Type of Contribution

• Bug fix
• New feature
• Documentation update
• Refactor
• GSSoC contribution

Participant Info

• GitHub username: Saylee12R
• Contribution level: Beginner

Screen Recording

Recording / Loom link:

onboarding.fixes.mov

Checklist

• I have read the contribution guidelines
• My changes follow the project structure
• I have tested my changes locally
• npm run lint passes (no ESLint errors)
• This PR is related to a valid issue
• Screen recording attached above

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[github-actions]

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• Linked the issue this PR closes (e.g. Closes #123)
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