feat: added table of contents component

[msaeedsaeedi]

Description

Added table of contents component in each blog post for the readers to navigate easily

Related Issues

Fixes #17
Closes #17

Type of Change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update (non-breaking change to README, docs, or guides)
• Refactoring (code reorganization, styling, or performance improvement with no user-facing changes)

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration.

• Local Build: Ran npm run build and compiled successfully with no errors.
• Lint/Format Check: Ran npm run lint and all Biome rules passed.
• Browser Testing: Tested and verified page rendering and interactions on (list browsers/devices):
  • Chrome / Firefox / Safari
  • Mobile viewports (if applicable)

If applicable, please attach screenshots or screen recordings demonstrating the visual/behavioral changes:

Checklist

• My code follows the style guidelines of this project (run npm run lint:fix and npm run format:write locally).
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation (if applicable).
• My changes generate no new warnings or console errors.
• I have linked any related issues.