feat: Invoice Editor improvements and code cleanup

Major Invoice Editor updates:
- ✅ Fixed tripled scrollbar issue by removing unnecessary overflow classes
- ✅ Implemented dynamic currency system with JSON data loading
- ✅ Fixed F4 PDF generation error with proper paper size handling
- ✅ Added proper padding to Total section matching table headers
- ✅ Removed print functionality (users can print from PDF download)
- ✅ Streamlined preview toolbar: Back, Size selector, Download PDF
- ✅ Fixed all ESLint warnings and errors
- ✅ Removed console.log statements across codebase for cleaner production
- ✅ Added border-top to Total section for better visual consistency
- ✅ Improved print CSS and removed JSX warnings

Additional improvements:
- Added currencies.json to public folder for proper HTTP access
- Enhanced MinimalTemplate with better spacing and layout
- Clean build with no warnings or errors
- Updated release notes with new features

src/index.css

@@ -7,6 +7,13 @@
 @layer base {
   html {
     font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
+    overflow-x: hidden;
+  }
+  
+  body {
+    overflow-x: hidden;
+    width: 100%;
+    max-width: 100vw;
   }
   
   code, pre {