Rebuild portfolio around shipped 2026 work

Replaces the MERN-only personal page with a focused product portfolio
covering the 3 live Play Store apps (Localyze, The Ledger Report,
Praarthana) and 2 production web apps (stockportfolio.pro, playship.pro).

- Clean dark single-page design (Inter + JetBrains Mono)
- Real Play Store icons and screenshots
- Stack grouped by Web / Mobile / On-Device AI / Infra
- Removed heavy unused media (PDFs, MP4s, oversized images)
- Placeholder YouTube embeds with TODO markers for Avi's own walkthroughs

Author: avisre