Add advanced XSS polyglot payloads and explanations to 2 - XSS Polyglot.md

[Gunashekar31742]

"In this section, I’ve added some of the most advanced and sophisticated XSS polyglot payloads that leverage multiple encoding techniques, context-breaking strategies, and multi-language injection methods. These payloads are crafted to bypass common security filters and input validation mechanisms, making them highly effective in real-world security testing scenarios.

The payloads include examples that combine HTML, JavaScript, CSS, and URL encoding, illustrating how attackers can craft injections that work across different browsers and contexts. I’ve also included explanations of the techniques used, such as merging comment styles, encoding entities, breaking out of confined contexts like <textarea> and <script>, and exploiting less common event handlers like onauxclick or ontoggle