refactor(auth): delegate access control to be-system

Remove Agent Desk users, roles, login sessions, tokens, and local permission persistence. Expose the backend as an embeddable ai-agent module with host-provided subject lookup and operation authorization callbacks, and complete the frontend/backend repository split.

internal/pkg/toolx/builtin_tools.go

@@ -3,8 +3,8 @@ package toolx
 import (
 	"strings"
 
-	"agent-desk/internal/pkg/enums"
-	"agent-desk/internal/pkg/i18nx"
+	"code.tczkiot.com/wlw/ai-agent/internal/pkg/enums"
+	"code.tczkiot.com/wlw/ai-agent/internal/pkg/i18nx"
 )
 
 type ToolSpec struct {

internal/pkg/toolx/builtin_tools_test.go

@@ -3,7 +3,7 @@ package toolx
 import (
 	"testing"
 
-	"agent-desk/internal/pkg/i18nx"
+	"code.tczkiot.com/wlw/ai-agent/internal/pkg/i18nx"
 )
 
 func TestResolveToolMetadata(t *testing.T) {

internal/pkg/toolx/mcp_policy.go

@@ -3,7 +3,7 @@ package toolx
 import (
 	"strings"
 
-	"agent-desk/internal/pkg/dto/request"
+	"code.tczkiot.com/wlw/ai-agent/internal/pkg/dto/request"
 )
 
 const (

internal/pkg/toolx/mcp_tool.go

@@ -4,8 +4,8 @@ import (
 	"encoding/json"
 	"strings"
 
-	"agent-desk/internal/pkg/dto/request"
-	"agent-desk/internal/pkg/errorsx"
+	"code.tczkiot.com/wlw/ai-agent/internal/pkg/dto/request"
+	"code.tczkiot.com/wlw/ai-agent/internal/pkg/errorsx"
 )
 
 func BuildMCPToolCode(serverCode, toolName string) string {