Refactor portfolio to a simpler and stable architecture

[utkuhanakar]

Problem

The current portfolio structure became overly complex and unstable.

Issues observed

• Multiple systems (entry, overlay, theme) conflict
• Hard to maintain and debug
• UI lost its simplicity

Goal

Rebuild the portfolio with:

• minimal structure
• clear separation of concerns
• stable interactions

Plan

• Remove unnecessary systems
• Keep only essential features
• Build step by step