Web UI: zone naming and reverse zones, ACL suggestions, record form

- New zone dialog: choose Domain or Reverse zone. Reverse zones are
  created from a network and their name is generated; both kinds show the
  exact zone name and flag likely mistakes (addresses or URLs as names,
  host-like names, duplicates in the view, parent/child zones, networks
  off the octet/nibble boundaries) before anything is submitted.
- Record form: clears every field but the type after an add; shows the
  record exactly as it will be stored and warns about unqualified names.
  In reverse zones it takes an address, defaults to PTR, suggests host
  names of A/AAAA records with that address and warns about a second PTR;
  the record list shows addresses.
- Address match lists (options, view match lists, ACL elements) offer the
  existing ACLs, TSIG keys and built-ins as one-click suggestions and
  flag unknown names.
- Server: in reverse zones a record can be named by its address, and a
  PTR target like nas.example.com without the final dot is read as the
  full host name (a bare label is refused). Warnings noticed while parsing
  record data reach the result again.
- Fixes: brand link hover underline, the dashboard's "New zone" link
  opening the dialog twice.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/web/static/assets/ui.js

@@ -131,8 +131,10 @@ export async function confirmDialog(title, message, okLabel = "OK", kind = "prim
 
 // field returns a label + control pair for .form-grid layouts.
 export function field(label, control, help) {
-  const id = control.id || ("f" + Math.random().toString(36).slice(2, 9));
-  control.id = id;
+  // The label points at the control itself, also when it is wrapped.
+  const target = control.matches && !control.matches("input, select, textarea") ? control.querySelector("input, select, textarea") || control : control;
+  const id = target.id || ("f" + Math.random().toString(36).slice(2, 9));
+  target.id = id;
   return [h("label", { for: id }, label), control, help ? h("div", { class: "help" }, help) : null];
 }