[Docs] Fixes and improvements across pages

[harishmohanraj]

Describe the issue

This issue addresses multiple improvements and bug fixes across the website, including:

• Fix callout boxes across all pages - @KadirCanTufek
• Implement automatic addition of author information to all blog pages - @harishmohanraj - PR#297
• Update headers in the API reference to use lowercase letters.- @harishmohanraj - PR#297
• Docs generation for /notebook/agentchat_graph_rag_neo4j.ipynb is failing- @harishmohanraj - PR#317
• Remove escaped characters (e.g., /{, /<) from the API reference documentation - @harishmohanraj - PR#317
• Fix the javascript console errors - @harishmohanraj - PR#318
• Remove unused Docusaurus-related files from the project - @harishmohanraj - PR#318
• Fix image display issues in the application gallery that occur in production but not locally (3 hr) - @harishmohanraj - PR#319
• Resolve tag filtering issues in the application gallery and notebook examples pages that work locally but not in production. (4 hr) - @harishmohanraj - PR#337

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Additional Information

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