Restructures all three dev targets (hiccup, replicant, squint) to use
the sidebar component as the actual app shell. The sidebar navigates
between three pages:
- Components — all UI component demos
- Icons — categorized gallery with all 50+ icons and size variants
- Sidebar — embedded sidebar example with dashboard layout
The sidebar includes a Targets section that links between all three dev
servers, with ports derived dynamically from the current port so they
stay correct when using a custom base port (bb dev-all 5000).
Port scheme: replicant=base+1, squint=base+2, hiccup=base+3.
Move font-family, background, color, margin, and transition from
duplicated inline <style> blocks in each dev target into the CSS
generator (base-css). Dev pages now only set page-specific padding.
Also fixes hiccup target rendering the wrong font due to hiccup2
HTML-escaping quotes inside <style> tags, and adds missing <!DOCTYPE>.
