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) <noreply@anthropic.com>

build/README.md

@@ -0,0 +1,35 @@
+# Build Directory
+
+The build directory is used to house all the build files and assets for your application. 
+
+The structure is:
+
+* bin - Output directory
+* darwin - macOS specific files
+* windows - Windows specific files
+
+## Mac
+
+The `darwin` directory holds files specific to Mac builds.
+These may be customised and used as part of the build. To return these files to the default state, simply delete them
+and
+build with `wails build`.
+
+The directory contains the following files:
+
+- `Info.plist` - the main plist file used for Mac builds. It is used when building using `wails build`.
+- `Info.dev.plist` - same as the main plist file but used when building using `wails dev`.
+
+## Windows
+
+The `windows` directory contains the manifest and rc files used when building with `wails build`.
+These may be customised for your application. To return these files to the default state, simply delete them and
+build with `wails build`.
+
+- `icon.ico` - The icon used for the application. This is used when building using `wails build`. If you wish to
+  use a different icon, simply replace this file with your own. If it is missing, a new `icon.ico` file
+  will be created using the `appicon.png` file in the build directory.
+- `installer/*` - The files used to create the Windows installer. These are used when building using `wails build`.
+- `info.json` - Application details used for Windows builds. The data here will be used by the Windows installer,
+  as well as the application itself (right click the exe -> properties -> details)
+- `wails.exe.manifest` - The main application manifest file.