feature: added request body size limiting middleware

[Jeet-Srivastava]

• Add BodySizeLimit middleware to prevent DoS attacks from large request bodies
• Configurable via HTTP_MAX_BODY_SIZE environment variable (default: 10 MB)
• Returns HTTP 413 when request body exceeds limit
• Comprehensive test coverage including unit and integration tests
• Follows GoFr middleware patterns and coding standards

Description:

• Provide a concise explanation of the changes made.
• Mention the issue number(s) this PR addresses (if applicable).
• Highlight the motivation behind the changes and the expected benefits.

Breaking Changes (if applicable):

• List any breaking changes introduced by this PR.
• Explain the rationale behind these changes and how they will impact users.

Additional Information:

• Mention any relevant dependencies or external libraries used.
• Include screenshots or code snippets (if necessary) to clarify the changes.

Checklist:

• I have formatted my code using goimport and golangci-lint.
• All new code is covered by unit tests.
• This PR does not decrease the overall code coverage.
• I have reviewed the code comments and documentation for clarity.

[aryanmehrotra]

@Jeet-Srivastava which issue ticket is this related to?

[Jeet-Srivastava]

Hi @aryanmehrotra
This feature was self-initiated and isn’t linked to a specific issue.
If you think it adds value, I’d be grateful if you could consider merging it.

@Jeet-Srivastava which issue ticket is this related to?

[Umang01-hash]

@Jeet-Srivastava Thankyou for your contribution to GoFr and taking an effort to make this PR. I would request you to please also create an issue describing how GoFr is prone to DoS from large request bodies, and then i think you can link this PR in that issue that will make perfect sense.

Secondly i would also request you to kindly resolve the code quality issues and the failing tests for the PR so that it is review ready. Please let us know if you need any assistance.

Thankyou.

[Jeet-Srivastava]

This PR is raised agains the issue #2607