fix: use PNG Gitcord logo to fix display error

- Replace public/gitcord.svg with public/gitcord.png (correct format)
- Update README to reference gitcord.png

Made-with: Cursor

Author: shubham5080

README.md

@@ -4,7 +4,7 @@
 <!-- Organization Logo -->
 <div align="center" style="display: flex; align-items: center; justify-content: center; gap: 16px;">
   <img alt="AOSSIE" src="public/aossie-logo.svg" width="175">
-  <img alt="Gitcord" src="public/gitcord.svg" width="175" />
+  <img alt="Gitcord" src="public/gitcord.png" width="175" />
 </div>
 
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