Update summary.en.md

Author: alisolphp

books/The Clinician's Handbook/summary.en.md

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 This document summarizes the key lessons and insights extracted from the book.
 I highly recommend reading the original book for the full depth and author's perspective.
 
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 ## Before You Get Started
 * I summarize key points from useful books to learn and review quickly.
 * Simply click on `Ask AI` links after each section to dive deeper.