Enhancement: Implement Post Modification Functionality

[zablon-oigo]

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Issue Description:
I would like to propose the implementation of a post-modification feature on the project. Currently, there is no way for the authors of posts to update their content. I believe adding this functionality will enhance user experience and engagement on the platform.

Suggested Implementation:

• Create a new template update.html with a form to edit the post content.
• Include an "Update Post" button on the post details page.
• Implement server-side logic to handle the update, ensuring that only the original author can modify their post.

Additional Context:
In many scenarios, users may want to correct errors or update information in their posts after publication. This feature would provide a valuable addition to the platform, promoting user autonomy and improving overall content quality.

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@Akash1362000 Please assign me to work on it

[Akash1362000]

@zablon-oigo Sure. That would be great! You can start working on it and raise a PR once the feature is implemented.