Refactor/cleanup errors

[HJLebbink]

refactored errors to create a higher level Error and four lower level errors

[Copilot]

Pull Request Overview

This PR refactors the error handling system to create a hierarchical error structure, replacing a single flat Error enum with a higher-level Error enum and four specialized error types: ValidationErr, S3ServerError, ReqwestError, and IoError.

• Error hierarchy restructuring: Replaced monolithic Error enum with specialized error types for better error categorization and handling
• Header constant consolidation: Centralized HTTP header constants in a dedicated module to improve consistency and maintainability
• Testing improvements: Enhanced test structure with helper functions and additional test cases for edge cases like whitespace handling

Reviewed Changes

Copilot reviewed 131 out of 131 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/s3/error.rs	Complete restructure of error types into hierarchical system
src/s3/header_constants.rs	New module containing all HTTP header constants
src/s3/minio_error_response.rs	New module for S3-specific error responses and error codes
tests/*	Multiple test files refactored with helper functions and additional test cases
src/s3/utils.rs	Updated utility functions to use new error types and URL encoding

Comments suppressed due to low confidence (1)

src/s3/utils.rs:27

• This type alias is defined but never used in the diff. Consider removing it if it's not needed.

use md5::compute as md5compute;

[donatello]

This is great! please fix conflicts.

[HJLebbink]

@donatello fixed merge issues. PTAL