feat: add custom Bootstrap styling with SCSS support

Implement SCSS-based custom styling system to enable Bootstrap customization while maintaining CDN delivery for core framework.

Changes:
- Add Hugo Pipes SCSS processing pipeline using css.Sass
- Create modular SCSS file structure (main.scss, _variables.scss, _custom.scss)
- Implement custom typography (base font size 1.25rem, adjusted heading sizes)
- Add custom link colors (#0b0089 primary, #0052a3 hover)
- Configure CSS minification and SHA-384 fingerprinting for cache busting
- Add comprehensive SCSS styling documentation

Technical details:
- Updated baseof.html to compile SCSS with Hugo Pipes
- CSS loads after Bootstrap CDN for proper cascade
- Minified output (~154 bytes)
- Supports live reload in development mode

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

assets/scss/_custom.scss

@@ -0,0 +1,14 @@
+// Custom Component Styles
+// Add custom styles that extend or modify Bootstrap components
+
+// Example: Custom navbar styling
+// .navbar-brand {
+//   font-weight: 700;
+// }
+
+// Example: Custom card styling
+// .card {
+//   border-radius: 8px;
+// }
+
+// Add your custom styles here