feat: redesign portfolio to bryl-minimal aesthetic and refine mobile/desktop UX

- Default theme to system mode with live OS color-scheme detection
- Fix custom dot-matrix sprite cursor for light/dark modes
- Preserve natural color portraits across all views
- Improve mobile hero layout with responsive portrait and Geist Pixel typography
- Add subtle color tint to perimeter background dots while keeping reading content clear
- Center certificate modal via createPortal and make verify button theme-responsive
- Make settings controls (magnifier toggle, lens button, zoom levels) theme-responsive
- Remove flagship badge and deep-dive technical sections from TIS-RMS case study

package.json

@@ -19,8 +19,11 @@
     "@emnapi/core": "^1.11.3",
     "@emnapi/runtime": "^1.11.3",
     "@emnapi/wasi-threads": "^2.2.0",
+    "@fontsource-variable/geist": "^5.3.0",
+    "@fontsource-variable/geist-mono": "^5.3.0",
     "@fontsource-variable/inter": "^5.3.0",
     "@fontsource-variable/jetbrains-mono": "^5.3.0",
+    "@fontsource-variable/source-serif-4": "^5.3.1",
     "@fontsource/dotgothic16": "^5.3.1",
     "@fortawesome/fontawesome-free": "^7.3.1",
     "@fortawesome/fontawesome-svg-core": "^7.3.1",
@@ -34,6 +37,7 @@
     "@types/react-dom": "^19.2.3",
     "astro": "^7.0.6",
     "framer-motion": "^12.42.2",
+    "geist": "^1.8.2",
     "ogl": "^1.0.11",
     "react": "^19.2.7",
     "react-dom": "^19.2.7",