feat: /neural nav entry + e2e spec

e2e/neural.spec.ts

@@ -0,0 +1,23 @@
+// /neural demo — plumbing assertions (no model download: UI + error surfaces).
+import { expect, test } from "@playwright/test"
+
+test("neural demo renders controls and surfaces errors with causes", async ({ page }) => {
+  await page.goto("/neural")
+  await expect(page.getByRole("heading", { name: "Neural models demo" })).toBeVisible()
+  await expect(page.locator("#model")).toHaveValue(/ara-diac-small/)
+  await expect(page.locator("#run")).toBeEnabled()
+  // An unknown model id yields a RegistryError surfaced with its cause chain.
+  await page.selectOption("#model", "ara-diac-small-2.0-int8")
+  await page.evaluate(() => {
+    const s = document.getElementById("model")! as HTMLSelectElement
+    s.value = "nope-9.9"
+  })
+  await page.click("#run")
+  await expect(page.locator("#output")).toContainText(/unknown model id|Error/, { timeout: 60_000 })
+})
+
+test("clear-cache reports state", async ({ page }) => {
+  await page.goto("/neural")
+  await page.click("#clear-cache")
+  await expect(page.locator("#confidence")).toContainText(/cleared/i)
+})

src/layouts/Base.astro

@@ -274,6 +274,7 @@ const slug = (label: string) => label.toLowerCase().replace(/\s+/g, "-")
               <li><a href="/demo">Live transliteration</a></li>
               <li><a href="/maps">Map catalogue</a></li>
               <li><a href="/ml">Model catalogue</a></li>
+              <li><a href="/neural">Neural demo</a></li>
               <li><a href="/authorities">Authorities</a></li>
               <li><a href="/docs">Documentation</a></li>
               <li><a href="/docs/phonological-layer">Phonological layer</a></li>