feat(tenant-api): expose Swagger UI in non-release mode

Adds an in-process Swagger UI and OpenAPI JSON under /swagger,
registered automatically when the Gin mode is not release. The
admin-web Vite dev server and production nginx config now proxy
/swagger to the tenant API so the docs are reachable from the
existing admin host.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

server/internal/tenant/transport/router.go

@@ -4,6 +4,7 @@ import (
 	"github.com/geo-platform/tenant-api/internal/bootstrap"
 	"github.com/geo-platform/tenant-api/internal/shared/auth"
 	"github.com/geo-platform/tenant-api/internal/shared/middleware"
+	"github.com/geo-platform/tenant-api/internal/shared/swagger"
 	"github.com/geo-platform/tenant-api/internal/tenant/repository"
 )
 
@@ -245,4 +246,11 @@ func RegisterRoutes(app *bootstrap.App) {
 	imageFolders.PUT("/:id", imgHandler.UpdateFolder)
 	imageFolders.GET("/:id/delete-preview", imgHandler.FolderDeletePreview)
 	imageFolders.DELETE("/:id", imgHandler.DeleteFolder)
+
+	if swagger.EnabledForMode(app.Config.Server.Mode) {
+		swagger.Register(app.Engine, swagger.Config{
+			Title:   "Geo Rankly Admin API",
+			Version: "dev",
+		})
+	}
 }