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/ui/tooltip.tsx

@@ -0,0 +1,25 @@
+import * as React from 'react';
+import * as TooltipPrimitive from '@radix-ui/react-tooltip';
+import { cn } from '@/lib/utils';
+
+const TooltipProvider = TooltipPrimitive.Provider;
+const Tooltip = TooltipPrimitive.Root;
+const TooltipTrigger = TooltipPrimitive.Trigger;
+
+const TooltipContent = React.forwardRef<
+  React.ElementRef<typeof TooltipPrimitive.Content>,
+  React.ComponentPropsWithoutRef<typeof TooltipPrimitive.Content>
+>(({ className, sideOffset = 4, ...props }, ref) => (
+  <TooltipPrimitive.Content
+    ref={ref}
+    sideOffset={sideOffset}
+    className={cn(
+      'z-50 overflow-hidden rounded-md bg-stone-900 px-2.5 py-1.5 text-xs text-white shadow-md animate-in fade-in-0 zoom-in-95 data-[state=closed]:animate-out data-[state=closed]:fade-out-0 data-[state=closed]:zoom-out-95 data-[side=bottom]:slide-in-from-top-2 data-[side=left]:slide-in-from-right-2 data-[side=right]:slide-in-from-left-2 data-[side=top]:slide-in-from-bottom-2',
+      className,
+    )}
+    {...props}
+  />
+));
+TooltipContent.displayName = TooltipPrimitive.Content.displayName;
+
+export { Tooltip, TooltipTrigger, TooltipContent, TooltipProvider };