Show company logo instead of chart icon on auth and dashboard pages

Replaces ChartLine icons with logo images in AuthPage and EnhancedSidebar components.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: d5daeb82-020f-4ea2-a54f-9097efac2a63
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/4119c42c-9857-448a-8c94-20be047485ba/1349e612-18a3-460c-9f34-a14280adb5a9.jpg