docs: modernize rclone.org site design

- replace Bootstrap/jQuery with purpose-built CSS and JS
- remove backend icons from navbar and content pages
- replace remaining FontAwesome icons with inline SVGs, remove FontAwesome
- modernize CSS styling for menus, typography, cards, tables, and code blocks
- add copy-to-clipboard buttons on code blocks using SVG icon
- move TOC to left sidebar with responsive overlay drawer
- add sticky header, top scrollbar and first column for wide tables
- add left/right arrow buttons to scrollable tables
- hide homepage logo on mobile
- make wide menus with filter for Commands and Storage Systems
- add dark mode support based on browser preference
- fix CSS/JS cache busting to use build time

docs/content/local.md

@@ -4,7 +4,7 @@ description: "Rclone docs for the local filesystem"
 versionIntroduced: "v0.91"
 ---
 
-# {{< icon "fas fa-hdd" >}} Local Filesystem
+# Local Filesystem
 
 Local paths are specified as normal filesystem paths, e.g. `/path/to/wherever`, so