Replace logo.svg with codelens-brand-v2.svg

Add a new brand asset (assets/codelens-brand-v2.svg), remove the old assets/logo.svg, and update README.md to reference the new SVG. The new asset updates the logo dimensions and refreshed styling (400x100) to reflect updated branding.

README.md

@@ -1,5 +1,5 @@
 <p align="center">
-  <img src="assets/logo.svg" width="400" alt="CodeLens." />
+  <img src="assets/codelens-brand-v2.svg" width="400" alt="CodeLens." />
 </p>
 
 # CodeLens