fix: surface out_of_range error for unsupported HDMI resolution (>1080p)

native.go

@@ -37,6 +37,7 @@ func initNative(systemVersion *semver.Version, appVersion *semver.Version) {
 			_ = reapplyHostDisplayAdvertisement("native_restarted")
 		},
 		OnVideoStateChange: func(state native.VideoState) {
+			state = unsupportedResolutionState(state)
 			lastVideoState = state
 			triggerVideoStateUpdate()
 			requestDisplayUpdate(false, "video_state_changed")

video.go

@@ -37,6 +37,14 @@ func rpcGetVideoState() (native.VideoState, error) {
 	return lastVideoState, nil
 }
 
+func unsupportedResolutionState(state native.VideoState) native.VideoState {
+	if state.Error == "" && (state.Width > 1920 || state.Height > 1080) {
+		state.Error = "out_of_range"
+		state.Ready = false
+	}
+	return state
+}
+
 var (
 	hostDisplayAdvertiseLock = sync.Mutex{}
 	hostDisplayAdvertised    bool

video_test.go

@@ -0,0 +1,47 @@
+//go:build linux && arm
+
+package kvm
+
+import (
+	"testing"
+
+	"github.com/jetkvm/kvm/internal/native"
+)
+
+func TestUnsupportedResolutionState(t *testing.T) {
+	tests := []struct {
+		name  string
+		input native.VideoState
+		want  native.VideoState
+	}{
+		{
+			name:  "1920x1080 no error unchanged",
+			input: native.VideoState{Ready: true, Width: 1920, Height: 1080},
+			want:  native.VideoState{Ready: true, Width: 1920, Height: 1080},
+		},
+		{
+			name:  "3840x2160 no error becomes out_of_range",
+			input: native.VideoState{Ready: true, Width: 3840, Height: 2160},
+			want:  native.VideoState{Ready: false, Error: "out_of_range", Width: 3840, Height: 2160},
+		},
+		{
+			name:  "1920x1080 no_signal unchanged",
+			input: native.VideoState{Ready: false, Error: "no_signal", Width: 1920, Height: 1080},
+			want:  native.VideoState{Ready: false, Error: "no_signal", Width: 1920, Height: 1080},
+		},
+		{
+			name:  "3840x2160 no_lock keeps no_lock",
+			input: native.VideoState{Ready: false, Error: "no_lock", Width: 3840, Height: 2160},
+			want:  native.VideoState{Ready: false, Error: "no_lock", Width: 3840, Height: 2160},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := unsupportedResolutionState(tt.input)
+			if got != tt.want {
+				t.Errorf("unsupportedResolutionState(%+v) = %+v, want %+v", tt.input, got, tt.want)
+			}
+		})
+	}
+}