chore: bump react/vue/svelte consumers to vite 8 (+ fix 2 regressions)

Moves the three plugin-gated consumers from vite 5/6 → 8.1.0 (Rollup →
Rolldown), with framework plugins bumped to their vite-8 majors:
plugin-react ^4→^6, plugin-vue ^5→^6, vite-plugin-svelte ^5→^7.

Two real Vite-8 regressions surfaced and fixed:

1. React null-dispatcher crash (react-vite). plugin-react 6 + Rolldown no
   longer auto-dedupes React, so a workspace React copy got double-bundled
   → `Cannot read properties of null (reading 'useRef')` at first render,
   blanking the app. Added explicit resolve.dedupe (mirrors the existing
   vite.config.swc.ts which already documented this exact failure).

2. e2e IPv6/IPv4 desync (all three). Vite 8 binds `vite preview` to IPv6
   [::1] by default; Playwright's port-probe hits IPv4 127.0.0.1 → readiness
   hang. Pinned preview host + webServer.url + baseURL to explicit 127.0.0.1.

Verified per consumer: build + typecheck + full e2e green —
react 23/23, vue 10/10, svelte 17/17. solid/lit (already on 8.1, no
plugin gate) unchanged and re-verified 10/10 + 14/14.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KSYH6VBAJwa7nYy4AksuNH

Author: serpentblade

examples/consumers/react-vite/package.json

@@ -9,7 +9,7 @@
     "build": "vite build",
     "build:swc": "vite build --config vite.config.swc.ts",
     "build:preact": "vite build --config vite.config.preact.ts",
-    "preview": "vite preview --port 4174",
+    "preview": "vite preview --port 4174 --host 127.0.0.1",
     "typecheck": "tsc --noEmit",
     "test:e2e": "playwright test",
     "test:e2e:swc": "VITE_USE_SWC=1 playwright test",
@@ -33,13 +33,13 @@
     "@types/node": "^20",
     "@types/react": "^19.2.14",
     "@types/react-dom": "^19.2.3",
-    "@vitejs/plugin-react": "^4",
+    "@vitejs/plugin-react": "^6",
     "@vitejs/plugin-react-swc": "^4",
     "eslint": "^9",
     "eslint-plugin-react-hooks": "^5",
     "playwright": "^1",
     "source-map-js": "^1.2.1",
     "typescript": "^5.6",
-    "vite": "^5"
+    "vite": "^8"
   }
 }

examples/consumers/react-vite/playwright.config.ts

@@ -27,12 +27,15 @@ export default defineConfig({
   testDir: './tests/e2e',
   timeout: 30_000,
   use: {
-    baseURL: 'http://localhost:4174',
+    baseURL: 'http://127.0.0.1:4174',
     trace: 'on-first-retry',
   },
   webServer: {
     command: buildCommand,
-    port: 4174,
+    // Vite 8 (Rolldown) binds preview to IPv6 `[::1]` by default; pin the
+    // server + readiness probe + baseURL to explicit IPv4 127.0.0.1 so the
+    // ambiguous `localhost` (IPv6-first on Node 18+/macOS) can't desync them.
+    url: 'http://127.0.0.1:4174',
     reuseExistingServer: !process.env.CI,
     timeout: 120_000,
   },

examples/consumers/react-vite/vite.config.ts

@@ -20,6 +20,15 @@ export default defineConfig({
     Rozie({ target: 'react' }),
     react(),
   ],
+  // @vitejs/plugin-react 6 + Vite 8 (Rolldown) no longer auto-dedupes React the
+  // way the Babel plugin did under Vite ≤7. In a pnpm workspace a runtime
+  // package can drag in its own React copy, so both get bundled and hooks read
+  // a null `ReactCurrentDispatcher` → `Cannot read properties of null (reading
+  // 'useRef')` at first render. Force every `import 'react'` to the consumer's
+  // single copy. Mirrors vite.config.swc.ts.
+  resolve: {
+    dedupe: ['react', 'react-dom'],
+  },
   build: {
     sourcemap: true, // DX-01 requirement — stack traces resolve to .rozie
   },

examples/consumers/svelte-vite/package.json

@@ -24,11 +24,11 @@
   },
   "devDependencies": {
     "@playwright/test": "^1",
-    "@sveltejs/vite-plugin-svelte": "^5.1.1",
+    "@sveltejs/vite-plugin-svelte": "^7",
     "@tsconfig/svelte": "^5",
     "playwright": "^1",
     "svelte-check": "^4",
     "typescript": "^5.6",
-    "vite": "^6"
+    "vite": "^8"
   }
 }

examples/consumers/svelte-vite/playwright.config.ts

@@ -13,12 +13,14 @@ export default defineConfig({
   testDir: './tests/e2e',
   timeout: 30_000,
   use: {
-    baseURL: 'http://localhost:4175',
+    baseURL: 'http://127.0.0.1:4175',
     trace: 'on-first-retry',
   },
+  // Vite 8 (Rolldown) binds preview to IPv6 `[::1]` by default; pin server +
+  // probe + baseURL to explicit IPv4 so ambiguous `localhost` can't desync them.
   webServer: {
-    command: 'pnpm build && pnpm preview --port 4175 --strictPort',
-    port: 4175,
+    command: 'pnpm build && pnpm preview --port 4175 --strictPort --host 127.0.0.1',
+    url: 'http://127.0.0.1:4175',
     reuseExistingServer: !process.env.CI,
     timeout: 120_000,
   },

examples/consumers/vue-vite/package.json

@@ -24,11 +24,11 @@
   },
   "devDependencies": {
     "@playwright/test": "^1",
-    "@vitejs/plugin-vue": "^5",
+    "@vitejs/plugin-vue": "^6",
     "playwright": "^1",
     "source-map-js": "^1.2.1",
     "typescript": "^5.6",
-    "vite": "^5",
+    "vite": "^8",
     "vue-tsc": "^2"
   }
 }

examples/consumers/vue-vite/playwright.config.ts

@@ -4,16 +4,18 @@ export default defineConfig({
   testDir: './tests/e2e',
   timeout: 30_000,
   use: {
-    baseURL: 'http://localhost:4173',
+    baseURL: 'http://127.0.0.1:4173',
     trace: 'on-first-retry',
   },
   // `pnpm build && pnpm preview --port 4173`:
   //   - `vite build` produces dist/ (production source maps verified by DX-01 e2e)
-  //   - `vite preview` serves dist/ at localhost:4173
+  //   - `vite preview` serves dist/ at 127.0.0.1:4173
   //   - reuseExistingServer in dev avoids re-build per test run
+  // Vite 8 (Rolldown) binds preview to IPv6 `[::1]` by default; pin server +
+  // probe + baseURL to explicit IPv4 so ambiguous `localhost` can't desync them.
   webServer: {
-    command: 'pnpm build && pnpm preview --port 4173 --strictPort',
-    port: 4173,
+    command: 'pnpm build && pnpm preview --port 4173 --strictPort --host 127.0.0.1',
+    url: 'http://127.0.0.1:4173',
     reuseExistingServer: !process.env.CI,
     timeout: 120_000,
   },