fix(openai): artifact selector 스트림을 분류 전 버퍼링한다

apps/edge/internal/openai/anthropic_stream.go

@@ -603,7 +603,10 @@ func (c *anthropicHotPathCodec) runInitialPresetTurn(
 		gate  hotPathSelectorGate
 		err   error
 	)
-	if c.stream {
+	selectorState := s.artifactFrontiers.selectorInstructionState(
+		runMeta["iop_logical_request_id"], s.edgeIDValue(),
+	)
+	if c.stream && selectorState == selectorInstructionNone {
 		outer := c.callerOuterTurn("", hotPathOutputTokenCap(runMeta))
 		if err := c.prepareProgressiveWriter(w, outer, false); err != nil {
 			return stage, false, err
@@ -612,6 +615,8 @@ func (c *anthropicHotPathCodec) runInitialPresetTurn(
 			r.Context(), dispatch, "anthropic", runMeta["iop_stage_id"], result, outer,
 		)
 	} else {
+		// Artifact selector calls are private IOP control data. Keep them buffered
+		// until classification expands them into caller-visible workspace writes.
 		stage, gate, err = s.collectPresetSelectorResult(r.Context(), dispatch, "anthropic", result)
 	}
 	if err != nil {

apps/edge/internal/openai/hot_path_anthropic_gate_test.go

@@ -12,6 +12,7 @@ import (
 	"testing"
 	"time"
 
+	"iop/packages/go/config"
 	iop "iop/proto/gen/iop"
 )
 
@@ -150,6 +151,40 @@ func TestHotPathAnthropicDirectStreamPreservesEmptyToolInput(t *testing.T) {
 	assertHotPathWaiting(t, srv, "msg-empty-tool-tool-1", "provider-zero-arg-tool")
 }
 
+func TestHotPathAnthropicArtifactSelectorBuffersPrivateCalls(t *testing.T) {
+	fixture := newScriptedLightFixture(t, "anthropic", false)
+	alternative := scriptedLightWorkspaceAlternative()
+	write := alternative.Operations["write"]
+	write.CreatesParents = true
+	alternative.Operations["write"] = write
+	preset := hotPathSelectorPreset([]string{config.ModeDirect, config.ModeLight})
+	preset.WorkspaceTools = []config.ExecutionWorkspaceToolAlternative{alternative}
+	fixture.server.SetExecutionPresets([]config.ExecutionPreset{preset})
+	fixture.service.responses[0] = func(requestID string) string {
+		return scriptedArtifactPair("anthropic", requestID)
+	}
+
+	response := fixture.requestWithOptions(64, true)
+	if response.Code != http.StatusOK || strings.Contains(response.Body.String(), `"type":"error"`) ||
+		strings.Contains(response.Body.String(), hotPathArtifactPairToolName) {
+		t.Fatalf("artifact selector leaked or failed: status=%d body=%s", response.Code, response.Body.String())
+	}
+	events := decodeHotPathAnthropicSSE(t, response.Body.String())
+	var writeCalls int
+	for _, event := range events {
+		if event.name != "content_block_start" {
+			continue
+		}
+		block := hotPathAnthropicMap(t, event.payload["content_block"])
+		if block["type"] == "tool_use" && block["name"] == "write_file" {
+			writeCalls++
+		}
+	}
+	if writeCalls != 2 {
+		t.Fatalf("caller-visible write calls=%d, want 2; body=%s", writeCalls, response.Body.String())
+	}
+}
+
 func TestHotPathAnthropicLightStreamAggregatesStages(t *testing.T) {
 	fixture := newScriptedLightFixture(t, "anthropic", false)
 	fixture.service.responses[4] = func(requestID string) string {