🐛 Fix timezone extraction for posix/right symlinks, add RunCommand guard for Windows

Strip posix/ and right/ prefixes from zoneinfo symlink targets so
/etc/localtime → .../zoneinfo/posix/Asia/Tokyo correctly returns
"Asia/Tokyo" instead of the invalid "posix/Asia/Tokyo".

Add Capability_RunCommand check to Windows date provider, matching
the Unix implementation, so static targets don't error.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: tas50

providers/os/resources/date/unix.go

@@ -134,9 +134,17 @@ func extractTZFromPath(path string) string {
 	const marker = "zoneinfo/"
 	if idx := strings.LastIndex(path, marker); idx >= 0 {
 		tz := path[idx+len(marker):]
-		if tz != "" && tz != "localtime" {
-			return tz
+		if tz == "" || tz == "localtime" {
+			return ""
 		}
+		// Strip posix/ and right/ prefixes — these are alternate
+		// representations of the same zones, not valid IANA names.
+		tz = strings.TrimPrefix(tz, "posix/")
+		tz = strings.TrimPrefix(tz, "right/")
+		if tz == "" {
+			return ""
+		}
+		return tz
 	}
 	return ""
 }

providers/os/resources/date/unix_test.go

@@ -104,9 +104,14 @@ func TestExtractTZFromPath(t *testing.T) {
 			want: "Europe/London",
 		},
 		{
-			name: "posix subdirectory path returns full relative",
+			name: "posix subdirectory path stripped",
 			path: "/usr/share/zoneinfo/posix/Asia/Tokyo",
-			want: "posix/Asia/Tokyo",
+			want: "Asia/Tokyo",
+		},
+		{
+			name: "right subdirectory path stripped",
+			path: "/usr/share/zoneinfo/right/Europe/Berlin",
+			want: "Europe/Berlin",
 		},
 		{
 			name: "no zoneinfo marker",

providers/os/resources/date/windows.go

@@ -30,6 +30,10 @@ func (w *Windows) Name() string {
 }
 
 func (w *Windows) Get() (*Result, error) {
+	if !w.conn.Capabilities().Has(shared.Capability_RunCommand) {
+		return &Result{Timezone: "UTC"}, nil
+	}
+
 	cmd, err := w.conn.RunCommand(powershell.Wrap(windowsDateCmd))
 	if err != nil {
 		return nil, fmt.Errorf("failed to get system date: %w", err)