test(e2e): add Cypress scaffold + CI job

frontend/cypress.config.ts

@@ -0,0 +1,11 @@
+import { defineConfig } from "cypress";
+
+export default defineConfig({
+  e2e: {
+    baseUrl: "http://localhost:3000",
+    video: false,
+    screenshotOnRunFailure: true,
+    specPattern: "cypress/e2e/**/*.cy.{ts,tsx,js,jsx}",
+    supportFile: "cypress/support/e2e.ts",
+  },
+});

frontend/cypress/e2e/activity_smoke.cy.ts

@@ -0,0 +1,7 @@
+describe("/activity page", () => {
+  it("loads without crashing", () => {
+    cy.visit("/activity");
+    // In secretless/unsigned state, UI should render the signed-out prompt.
+    cy.contains(/sign in to view the feed/i).should("be.visible");
+  });
+});

frontend/cypress/support/e2e.ts

@@ -0,0 +1,2 @@
+// Cypress support file.
+// Place global hooks/commands here.

frontend/package.json

@@ -10,7 +10,9 @@
     "test": "vitest run --passWithNoTests --coverage",
     "test:watch": "vitest",
     "dev:lan": "next dev --hostname 0.0.0.0 --port 3000",
-    "api:gen": "orval --config ./orval.config.ts"
+    "api:gen": "orval --config ./orval.config.ts",
+    "e2e": "cypress run",
+    "e2e:open": "cypress open"
   },
   "dependencies": {
     "@clerk/nextjs": "^6.37.1",
@@ -52,6 +54,7 @@
     "tailwindcss": "^3.4.17",
     "tailwindcss-animate": "^1.0.7",
     "typescript": "^5",
-    "vitest": "^2.1.8"
+    "vitest": "^2.1.8",
+    "cypress": "^14.0.0"
   }
 }