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/jchv/go-winloader/internal/winloader/hacks_windows.go

@@ -0,0 +1,73 @@
+package winloader
+
+import (
+	"errors"
+	"fmt"
+	"unsafe"
+
+	"golang.org/x/sys/windows"
+)
+
+var (
+	ntdllModule                    = windows.NewLazySystemDLL("ntdll")
+	ntdllNtQueryInformationProcess = ntdllModule.NewProc("NtQueryInformationProcess")
+)
+
+type _ProcessBasicInformation struct {
+	Reserved1       uintptr
+	PebBaseAddress  uintptr
+	Reserved2       [2]uintptr
+	UniqueProcessID uintptr
+	Reserved3       uintptr
+}
+
+type _PEB struct {
+	Reserved1     [2]byte
+	BeingDebugged byte
+	Reserved2     [1]byte
+	Reserved3     [2]uintptr
+	Ldr           uintptr
+}
+
+type _List struct {
+	Front uintptr
+	Back  uintptr
+}
+
+type _PEBLoaderData struct {
+	Length                          uint32
+	Initialized                     uint8
+	Padding                         [3]uint8
+	SsHandle                        uintptr
+	InLoadOrderModuleList           _List
+	InMemoryOrderModuleList         _List
+	InInitializationOrderModuleList _List
+}
+
+// MakePEBEntryForModule is a hack that inserts an entry for the loaded module
+// into the PEB loader data to make it appear to Windows functions.
+func MakePEBEntryForModule() error {
+	process := -1
+	sizeNeeded := uint32(0)
+	pbi := _ProcessBasicInformation{}
+	status, _, _ := ntdllNtQueryInformationProcess.Call(
+		uintptr(process),
+		0,
+		uintptr(unsafe.Pointer(&pbi)),
+		unsafe.Sizeof(pbi),
+		uintptr(unsafe.Pointer(&sizeNeeded)),
+	)
+	if status != 0 {
+		return fmt.Errorf("NtQueryInformationProcess failed: %08x", status)
+	}
+
+	// TODO: Implement attempt to insert module entry.
+	return errors.New("unimplemented")
+}
+
+// GetProcessHInstance gets the HINSTANCE for the current process.
+func GetProcessHInstance() (uintptr, error) {
+	var hinstance windows.Handle
+	windows.GetModuleHandleEx(0, nil, &hinstance)
+	return uintptr(hinstance), nil
+}