Switch remote deploy to vendored source builds

Move remote deployment to a vendored source bundle built on the target host via Docker so redeploys no longer require local cross-compilation or host Go installation.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

vendor/github.com/wailsapp/wails/v2/pkg/menu/callback.go

@@ -0,0 +1,8 @@
+package menu
+
+type CallbackData struct {
+	MenuItem *MenuItem
+	// ContextData string
+}
+
+type Callback func(*CallbackData)