Add callouts to LocallyGrown series for enhanced readability

Applied strategic callouts across all 4 posts in the LocallyGrown series:
- Info, success, warning, danger, tip, quote, and example callouts
- Improved visual hierarchy and information highlighting
- Better mobile readability with structured content blocks

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

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

assets/css/_extra.scss

@@ -13,4 +13,7 @@
     overflow-x: hidden !important;
     min-height: unset !important;
   }
-}
+}
+
+// Import callout styles
+@import 'callouts';