Merge "PATH" with Window's "Path".

This enables searching for exes in not just runtime PATH, but also Windows Path.

pkg/runtime/internal/envdef/environment.go

@@ -6,6 +6,7 @@ import (
 	"maps"
 	"os"
 	"path/filepath"
+	"runtime"
 	"strings"
 
 	"github.com/ActiveState/cli/internal/errs"
@@ -340,7 +341,11 @@ func (ed *EnvironmentDefinition) GetEnvBasedOn(envLookup map[string]string) (map
 	for _, ev := range ed.Env {
 		pev := &ev
 		if pev.Inherit {
-			osValue, hasOsValue := envLookup[pev.Name]
+			name := pev.Name
+			if runtime.GOOS == "windows" && name == "PATH" {
+				name = "Path" // env vars are case-insensitive on Windows, and this is what it uses
+			}
+			osValue, hasOsValue := envLookup[name]
 			if hasOsValue {
 				osEv := ev
 				osEv.Values = []string{osValue}