Removed numerous local image and document files from content posts and updated markdown files to reference external image and document URLs instead. This reduces repository size and centralizes media hosting, improving maintainability.

Added the content for Newsletter #58 in Vietnamese, covering topics such as productive decision-making for engineers, event-driven systems, developer culture, AI tool calls, logging secrets, and more. Included several illustrative images from ByteByteGo to accompany the post.