Revise README for FastPix iOS Uploads SDK

[ashutoshkhainar33-star]

Updated README to enhance SDK documentation with features, installation instructions, usage examples, and FAQs.

FastPix iOS Uploads SDK - Documentation PR

Documentation Changes

• New documentation added
• Existing documentation updated
• Documentation errors fixed
• Code examples updated
• Links and references updated

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Files Modified

• README.md
• docs/ directory
• USAGE.md
• CONTRIBUTING.md
• Other: _______________

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Summary

Brief description of changes:

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Code Examples

import fp_swift_upload_sdk

// Initialize Uploads instance for handling file uploads
var uploader = Uploads()

// Example: Upload a file using a signed URL from your backend
Task {
    let createUploadURL = try await self.myServerBackend.createDirectUpload()
    uploader.uploadFile(
        file: file!,
        endpoint: createUploadURL.absoluteString,
        chunkSizeKB: Int(chunkSize.text ?? "") ?? 0
    )
}

// Manage upload lifecycle
uploader.pause()  // Pause upload
uploader.resume() // Resume upload
uploader.abort()  // Abort upload

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Testing

• All code examples tested on iOS
• Links verified
• Grammar checked
• Formatting consistent

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Review Checklist

• Content is accurate
• Code examples work as expected
• Links are working
• Grammar is correct
• Formatting is consistent

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Ready for review!