build: pass -tags desktop,production to go build (Wails requirement)

Without these tags Wails aborts at startup with a "Wails applications
will not build without the correct build tags" MessageBox. Local
rebuild.sh, the cross-compile step in release.yml, and the windows
build step in build.yml all needed the flag — only the local Wails
dev wrapper was already passing it.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.gitea/workflows/build.yml

@@ -106,7 +106,9 @@ jobs:
           # flashes a console window. main.go calls AttachConsole on
           # startup so CLI invocations from cmd/PowerShell still print
           # to the parent terminal.
-          go build -trimpath -ldflags="-s -w -H=windowsgui \
+          # -tags desktop,production is REQUIRED by Wails (see release.yml).
+          go build -trimpath -tags "desktop,production" \
+            -ldflags="-s -w -H=windowsgui \
             -X main.Version=dev-${SHORT_SHA} \
             -X main.Commit=${SHORT_SHA} \
             -X main.BuildDate=${BUILD_DATE}" \