fix: cross-platform signal handling for Windows

internal/injector/injector.go

@@ -8,6 +8,8 @@ import (
 	"syscall"
 )
 
+// signals is defined in signals_unix.go and signals_windows.go
+
 // RunCommand executes a command with the provided secrets injected into the environment.
 // It handles signal forwarding and exit code propagation.
 func RunCommand(command string, args []string, secrets map[string]string) error {
@@ -33,8 +35,7 @@ func RunCommand(command string, args []string, secrets map[string]string) error
 
 	// Handle signals
 	sigs := make(chan os.Signal, 1)
-	// Notify on all common signals
-	signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM, syscall.SIGHUP)
+	signal.Notify(sigs, signals...)
 
 	// Start the command
 	if err := cmd.Start(); err != nil {

internal/injector/signals_unix.go

@@ -0,0 +1,10 @@
+//go:build !windows
+
+package injector
+
+import (
+	"os"
+	"syscall"
+)
+
+var signals = []os.Signal{syscall.SIGINT, syscall.SIGTERM, syscall.SIGHUP}

internal/injector/signals_windows.go

@@ -0,0 +1,14 @@
+//go:build windows
+
+package injector
+
+import (
+	"os"
+	"syscall"
+)
+
+// SIGTERM is included because signal.Notify delivers it on console shutdown events
+// (CTRL_CLOSE_EVENT, CTRL_LOGOFF_EVENT, CTRL_SHUTDOWN_EVENT). Note that forwarding
+// SIGTERM to child processes via Process.Signal is not supported on Windows —
+// the attempt will fail silently.
+var signals = []os.Signal{syscall.SIGINT, syscall.SIGTERM}