Run go mod tidy before build in all installers

go.sum was never committed (no local Go toolchain to generate it),
causing "missing go.sum entry" build failures on target hosts.
go mod tidy regenerates it automatically before go build.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

bootstrap.sh

@@ -67,6 +67,7 @@ fi
 
 echo "Building wireguard-ui-multi..."
 cd "$SRC_DIR"
+go mod tidy
 go build -o wireguard-ui-multi ./cmd/wireguard-ui-multi
 
 echo "Running native installer..."

scripts/install.sh

@@ -19,6 +19,7 @@ fi
 if [[ ! -f "$BIN_SRC" ]]; then
 	if [[ -d "./cmd/wireguard-ui-multi" ]] && command -v go >/dev/null 2>&1; then
 		echo "Binary not found, building from source with 'go build'..."
+		go mod tidy
 		go build -o "$BIN_SRC" ./cmd/wireguard-ui-multi
 	else
 		echo "Binary not found at $BIN_SRC and cannot build (need Go toolchain + source). Build it first, e.g.:" >&2

scripts/proxmox-install.sh

@@ -161,6 +161,7 @@ echo "Running native installer inside container..."
 pct exec "$VMID" -- bash -c "
 	set -e
 	cd /opt/wireguard-ui-multi-src
+	go mod tidy
 	go build -o wireguard-ui-multi ./cmd/wireguard-ui-multi
 	bash scripts/install.sh
 "