Spool page for NFC links, bridge address; vendor-first new spool form

- /s/<id> shows a spool: rest in Spoolman and CC2 Control, where it is,
  last booking, history, links to Spoolman and the tag generator.
- Setting "Adresse der Bridge"; the tag generator can put <address>/s/<id>
  on the tag, so an iPhone held to the roll opens that page.
- New spool: vendor and material chosen from Spoolman, the vendor's
  filaments offered, values taken from similar filaments, duplicates
  pointed out and never created twice.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_014GcEk5tkfFSYD6NTF66NkC

app/templates/base.html

@@ -42,6 +42,7 @@
   }
 }
 * { box-sizing: border-box; }
+[hidden] { display: none !important; }
 html { -webkit-text-size-adjust: 100%; }
 body { margin: 0; background: var(--bg); color: var(--ink); font: 15px/1.45 var(--font); -webkit-font-smoothing: antialiased;
   -webkit-tap-highlight-color: transparent; }