feat: harden portfolio and add SEO foundations

lib/project-health.test.ts

@@ -1,12 +1,10 @@
 import {
   createProjectHealthSnapshot,
-  filterLiveProjects,
-  isCurrentLiveCheck,
+  getDemoAvailability,
   type ProjectHealthSnapshot,
 } from "./project-health";
 
 describe("project health snapshot", () => {
-  const now = new Date("2026-07-10T12:00:00.000Z");
   const snapshot: ProjectHealthSnapshot = {
     checkedAt: "2026-07-10T11:55:00.000Z",
     projects: {
@@ -28,36 +26,42 @@ describe("project health snapshot", () => {
     },
   };
 
-  it("accepts only fresh final HTTP 200 HTML projects", () => {
-    expect(isCurrentLiveCheck(snapshot.projects.online, now)).toBe(true);
-    expect(isCurrentLiveCheck(snapshot.projects.redirect, now)).toBe(false);
-    expect(isCurrentLiveCheck(snapshot.projects.stale, now)).toBe(false);
-
+  it("classifies demo availability from the latest observation", () => {
+    expect(getDemoAvailability(null, undefined)).toBe("none");
+    expect(getDemoAvailability("https://demo.example", undefined)).toBe(
+      "unknown",
+    );
     expect(
-      filterLiveProjects(
-        [
-          { id: "online", featured: true },
-          { id: "redirect", featured: true },
-          { id: "stale", featured: true },
-          { id: "hidden", featured: false },
-        ],
-        snapshot,
-        now,
-      ).map((project) => project.id),
-    ).toEqual(["online"]);
-  });
-
-  it("fails closed when the snapshot is absent or expired", () => {
+      getDemoAvailability("https://demo.example", {
+        status: null,
+        contentType: null,
+        checkedAt: "2026-07-10T11:55:00.000Z",
+        error: "network unavailable",
+      }),
+    ).toBe("unknown");
     expect(
-      filterLiveProjects([{ id: "online", featured: true }], null, now),
-    ).toEqual([]);
+      getDemoAvailability("https://demo.example", snapshot.projects.online),
+    ).toBe("available");
     expect(
-      filterLiveProjects(
-        [{ id: "online", featured: true }],
-        { ...snapshot, checkedAt: "2026-07-10T10:00:00.000Z" },
-        now,
-      ),
-    ).toEqual([]);
+      getDemoAvailability("https://demo.example", snapshot.projects.redirect),
+    ).toBe("unavailable");
+    expect(
+      getDemoAvailability("https://demo.example", {
+        status: 200,
+        contentType: "application/json",
+        checkedAt: "2026-07-10T11:55:00.000Z",
+      }),
+    ).toBe("unavailable");
+    expect(
+      getDemoAvailability("https://demo.example", {
+        status: 200,
+        contentType: "text/html+custom; charset=utf-8",
+        checkedAt: "2026-07-10T11:55:00.000Z",
+      }),
+    ).toBe("unavailable");
+    expect(
+      getDemoAvailability("https://demo.example", snapshot.projects.stale),
+    ).toBe("available");
   });
 
   it("creates a fresh health snapshot when the stored result is unavailable", async () => {