- Home page is now just the print server overview, no more unrelated
network links (3D printers, Cockpit) left over from when this was a
general landing page.
- Navbar shows which section is active; Brother's per-printer buttons
now live under a dedicated Brother nav item instead of always-visible.
- Shipping labels: paste raw ZPL directly (no need to save to a file
first), with a Labelary preview link alongside it.
- Receipts: paste already-formatted ESC/POS text directly, printed as-is.
- Both can save what they just printed into a shared label repository
(lib/label_repository.rb, one JSON file per label under data/labels/)
for reprinting later -- saving happens independently of whether the
print itself succeeds, so a failed/offline printer doesn't lose the
content.
