Initial codebase: Go + Wails amateur radio logbook

Backend (Go 1.25 / Wails v2):
- QSO storage on SQLite (modernc) with embedded migrations (0001..0005)
- Streaming ADIF import (batch insert) + WorkedBefore per callsign and DXCC
- Callsign lookup with QRZ.com + HamQTH providers (primary/failsafe routing)
  and SQLite-backed TTL cache
- DXCC resolver from cty.dat (auto-download, longest-prefix-match)
- Multi-profile operator identities (home/portable/SOTA/contest) — every
  QSO stamps MY_* from the active profile
- CAT control via OmniRig COM on a single OS-locked goroutine, with
  bidirectional sync (freq/mode/band/split/VFOs) and Rig1/Rig2 hot-swap
- Settings store (key/value), CAT debug log at %APPDATA%/HamLog/cat.log

Frontend (React 18 + TypeScript + Tailwind v4 + shadcn-style):
- Single-row entry strip with CAT-aware band/mode/freq, RST, Start/End
  UTC, per-field locks (band/mode/freq/start/end) for backdated QSOs
- Topbar: live freq (MHz.kHz.Hz dotted), live UTC, band/mode/SPLIT badges,
  CAT pill with rig selector and clickable Azimuth pill (rotor TODO)
- Settings tree: Profiles (Log4OM-style manager), Station Information
  (edits the active profile), unified Callsign Lookup with Test buttons,
  Bands/Modes lists, CAT
- Worked-before matrix (band × mode × class) with new-DXCC highlighting
- ADIF import from menu + Maintenance > Refresh cty.dat

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

frontend/src/components/Menubar.tsx

@@ -0,0 +1,67 @@
+import { useState } from 'react';
+import {
+  DropdownMenu, DropdownMenuTrigger, DropdownMenuContent,
+  DropdownMenuItem, DropdownMenuSeparator, DropdownMenuShortcut,
+} from '@/components/ui/dropdown-menu';
+import { cn } from '@/lib/utils';
+
+export type MenuItem =
+  | { type: 'item'; label: string; action: string; shortcut?: string; disabled?: boolean }
+  | { type: 'separator' };
+
+export interface Menu {
+  name: string;
+  label: string;
+  items: MenuItem[];
+}
+
+interface Props {
+  menus: Menu[];
+  onAction: (action: string) => void;
+}
+
+export function Menubar({ menus, onAction }: Props) {
+  // Track which menu is open so hover-to-switch works like a desktop menubar.
+  const [openMenu, setOpenMenu] = useState<string | null>(null);
+
+  return (
+    <nav className="flex items-stretch h-full">
+      {menus.map((menu) => (
+        <DropdownMenu
+          key={menu.name}
+          open={openMenu === menu.name}
+          onOpenChange={(o) => setOpenMenu(o ? menu.name : null)}
+        >
+          <DropdownMenuTrigger
+            onMouseEnter={() => {
+              // Only switch on hover if a menu is already open.
+              if (openMenu !== null && openMenu !== menu.name) setOpenMenu(menu.name);
+            }}
+            className={cn(
+              'px-3 text-sm rounded-md text-muted-foreground hover:bg-muted hover:text-foreground transition-colors outline-none focus-visible:ring-2 focus-visible:ring-ring',
+              openMenu === menu.name && 'bg-muted text-primary',
+            )}
+          >
+            {menu.label}
+          </DropdownMenuTrigger>
+          <DropdownMenuContent align="start" sideOffset={4} className="min-w-[240px]">
+            {menu.items.map((item, i) =>
+              item.type === 'separator' ? (
+                <DropdownMenuSeparator key={i} />
+              ) : (
+                <DropdownMenuItem
+                  key={i}
+                  disabled={item.disabled}
+                  onSelect={() => onAction(item.action)}
+                >
+                  <span>{item.label}</span>
+                  {item.shortcut && <DropdownMenuShortcut>{item.shortcut}</DropdownMenuShortcut>}
+                </DropdownMenuItem>
+              ),
+            )}
+          </DropdownMenuContent>
+        </DropdownMenu>
+      ))}
+    </nav>
+  );
+}