强制启用文件拆分（实际模型忽略）

internal/config/config.go

@@ -100,6 +100,7 @@ func (c *Config) NormalizeCredentials() {
 	}
 
 	c.normalizeModelAliases()
+	c.forceHistorySplitEnabled()
 }
 
 // DropInvalidAccounts removes accounts that cannot be addressed by admin APIs
@@ -140,6 +141,14 @@ func (c *Config) normalizeModelAliases() {
 	}
 }
 
+func (c *Config) forceHistorySplitEnabled() {
+	if c == nil {
+		return
+	}
+	enabled := true
+	c.HistorySplit.Enabled = &enabled
+}
+
 type CompatConfig struct {
 	WideInputStrictOutput *bool `json:"wide_input_strict_output,omitempty"`
 	StripReferenceMarkers *bool `json:"strip_reference_markers,omitempty"`

internal/config/store_accessors.go

@@ -164,12 +164,7 @@ func (s *Store) AutoDeleteSessions() bool {
 }
 
 func (s *Store) HistorySplitEnabled() bool {
-	s.mu.RLock()
-	defer s.mu.RUnlock()
-	if s.cfg.HistorySplit.Enabled == nil {
-		return true
-	}
-	return *s.cfg.HistorySplit.Enabled
+	return true
 }
 
 func (s *Store) HistorySplitTriggerAfterTurns() int {

internal/config/store_accessors_test.go

@@ -18,10 +18,25 @@ func TestStoreHistorySplitAccessors(t *testing.T) {
 		TriggerAfterTurns: &turns,
 	}
 
-	if store.HistorySplitEnabled() {
-		t.Fatal("expected history split disabled after override")
+	if !store.HistorySplitEnabled() {
+		t.Fatal("expected history split to stay enabled after legacy disabled override")
 	}
 	if got := store.HistorySplitTriggerAfterTurns(); got != 3 {
 		t.Fatalf("history split trigger_after_turns=%d want=3", got)
 	}
 }
+
+func TestStoreHistorySplitLegacyDisabledConfigNormalizesToEnabled(t *testing.T) {
+	t.Setenv("DS2API_CONFIG_JSON", `{"keys":["k1"],"history_split":{"enabled":false,"trigger_after_turns":2}}`)
+	store := LoadStore()
+	if !store.HistorySplitEnabled() {
+		t.Fatal("expected history split enabled when legacy config disables it")
+	}
+	snap := store.Snapshot()
+	if snap.HistorySplit.Enabled == nil || !*snap.HistorySplit.Enabled {
+		t.Fatalf("expected normalized history_split.enabled=true, got %#v", snap.HistorySplit.Enabled)
+	}
+	if got := store.HistorySplitTriggerAfterTurns(); got != 2 {
+		t.Fatalf("history split trigger_after_turns=%d want=2", got)
+	}
+}

internal/httpapi/admin/handler_settings_test.go

@@ -189,8 +189,8 @@ func TestUpdateSettingsHistorySplit(t *testing.T) {
 		t.Fatalf("expected 200, got %d body=%s", rec.Code, rec.Body.String())
 	}
 	snap := h.Store.Snapshot()
-	if snap.HistorySplit.Enabled == nil || *snap.HistorySplit.Enabled {
-		t.Fatalf("expected history_split.enabled=false, got %#v", snap.HistorySplit.Enabled)
+	if snap.HistorySplit.Enabled == nil || !*snap.HistorySplit.Enabled {
+		t.Fatalf("expected history_split.enabled to be forced true, got %#v", snap.HistorySplit.Enabled)
 	}
 	if snap.HistorySplit.TriggerAfterTurns == nil || *snap.HistorySplit.TriggerAfterTurns != 3 {
 		t.Fatalf("expected history_split.trigger_after_turns=3, got %#v", snap.HistorySplit.TriggerAfterTurns)

internal/httpapi/admin/settings/handler_settings_parse.go

@@ -152,10 +152,8 @@ func parseSettingsUpdateRequest(req map[string]any) (*config.AdminConfig, *confi
 
 	if raw, ok := req["history_split"].(map[string]any); ok {
 		cfg := &config.HistorySplitConfig{}
-		if v, exists := raw["enabled"]; exists {
-			b := boolFrom(v)
-			cfg.Enabled = &b
-		}
+		enabled := true
+		cfg.Enabled = &enabled
 		if v, exists := raw["trigger_after_turns"]; exists {
 			n := intFrom(v)
 			if err := config.ValidateIntRange("history_split.trigger_after_turns", n, 1, 1000, true); err != nil {

internal/httpapi/openai/history/history_split.go

@@ -27,9 +27,6 @@ func (s Service) Apply(ctx context.Context, a *auth.RequestAuth, stdReq promptco
 	if s.DS == nil || s.Store == nil || a == nil {
 		return stdReq, nil
 	}
-	if !s.Store.HistorySplitEnabled() {
-		return stdReq, nil
-	}
 
 	promptMessages, historyMessages := SplitOpenAIHistoryMessages(stdReq.Messages, s.Store.HistorySplitTriggerAfterTurns())
 	if len(historyMessages) == 0 {