refactor: split backend into standalone server project

Remove embedded frontend and workflow editor assets, add standalone API deployment configuration, and retain the current backend service updates.

internal/bootstrap/db_test.go

@@ -4,8 +4,47 @@ import (
 	"os"
 	"path/filepath"
 	"testing"
+
+	"agent-desk/internal/pkg/config"
 )
 
+func TestNewDialector(t *testing.T) {
+	t.Parallel()
+
+	cases := []struct {
+		dbType string
+		want   string
+	}{
+		{dbType: "sqlite", want: "sqlite"},
+		{dbType: "mysql", want: "mysql"},
+		{dbType: "postgres", want: "postgres"},
+		{dbType: "postgresql", want: "postgres"},
+		{dbType: " PostgreSQL ", want: "postgres"},
+	}
+
+	for _, tt := range cases {
+		tt := tt
+		t.Run(tt.dbType, func(t *testing.T) {
+			t.Parallel()
+			dialector, err := newDialector(config.DBConfig{Type: tt.dbType, DSN: ":memory:"})
+			if err != nil {
+				t.Fatalf("newDialector() error = %v", err)
+			}
+			if got := dialector.Name(); got != tt.want {
+				t.Fatalf("dialector.Name() = %q, want %q", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestNewDialectorRejectsUnsupportedType(t *testing.T) {
+	t.Parallel()
+
+	if _, err := newDialector(config.DBConfig{Type: "oracle"}); err == nil {
+		t.Fatal("newDialector() error = nil, want unsupported type error")
+	}
+}
+
 func TestSQLiteFilePath(t *testing.T) {
 	t.Parallel()