fix: vite 6 breaking change for ssr module hmr, add migration plugin

packages/engine/src/plugin.ts

@@ -17,6 +17,7 @@ import type { GracileConfig } from './user-config.js';
 import { buildRoutes } from './vite/build-routes.js';
 import { htmlRoutesLoader } from './vite/html-routes.js';
 import { virtualRoutes, virtualRoutesClient } from './vite/virtual-routes.js';
+import { hmrSsrReload } from './vite/hmr.js';
 
 let isClientBuilt = false;
 
@@ -103,6 +104,8 @@ export const gracile = (config?: GracileConfig): any[] => {
 		// 			},
 		// 		},
 
+		hmrSsrReload(),
+
 		{
 			name: 'vite-plugin-gracile-serve-middleware',
 

packages/engine/src/vite/hmr.ts

@@ -0,0 +1,40 @@
+import type { Plugin, EnvironmentModuleNode } from 'vite';
+
+// NOTE: From https://vite.dev/guide/migration#advanced (Vite 5>6 migration).
+export function hmrSsrReload(): Plugin {
+	return {
+		name: 'vite-plugin-gracile-hmr-ssr-reload',
+		enforce: 'post',
+
+		hotUpdate: {
+			order: 'post',
+
+			handler({ modules, server, timestamp }) {
+				if (this.environment.name !== 'ssr') return;
+
+				let hasSsrOnlyModules = false;
+
+				const invalidatedModules = new Set<EnvironmentModuleNode>();
+				for (const module_ of modules) {
+					if (module_.id == null) continue;
+					const clientModule =
+						server.environments.client.moduleGraph.getModuleById(module_.id);
+					if (clientModule != null) continue;
+
+					this.environment.moduleGraph.invalidateModule(
+						module_,
+						invalidatedModules,
+						timestamp,
+						true,
+					);
+					hasSsrOnlyModules = true;
+				}
+
+				if (hasSsrOnlyModules) {
+					server.ws.send({ type: 'full-reload' });
+					return [];
+				}
+			},
+		},
+	};
+}

packages/engine/src/vite/virtual-routes.ts

@@ -87,7 +87,7 @@ export { routes, routeImports, routeAssets };
 
 				return null;
 			},
-		} satisfies Plugin,
+		},
 	];
 }
 
@@ -154,6 +154,6 @@ export { routeImports };
 
 				return null;
 			},
-		} satisfies Plugin,
+		},
 	];
 }