test(visual): allow playwright port override and rebaseline connections-mobile

Add PLAYWRIGHT_PORT env var to playwright.config.js so a worktree can run
its own dev server on a different port without disrupting the main dev
server. Rebaseline connections-mobile-auth which had drifted from the
suggestions data state captured during Phase 1.

playwright.config.js

@@ -1,5 +1,8 @@
 import { defineConfig } from "@playwright/test";
 
+const PORT = process.env.PLAYWRIGHT_PORT || "3000";
+const BASE_URL = `http://localhost:${PORT}`;
+
 export default defineConfig({
   testDir: "./e2e",
   outputDir: "e2e/test-results",
@@ -11,7 +14,7 @@ export default defineConfig({
   reporter: "html",
   timeout: 60000,
   use: {
-    baseURL: "http://localhost:3000",
+    baseURL: BASE_URL,
     trace: "on-first-retry",
     navigationTimeout: 45000,
   },
@@ -22,8 +25,8 @@ export default defineConfig({
     },
   ],
   webServer: {
-    command: "npm run build && NODE_ENV=development npm run preview",
-    url: "http://localhost:3000",
+    command: `PORT=${PORT} npm run build && PORT=${PORT} NODE_ENV=development npm run preview`,
+    url: BASE_URL,
     reuseExistingServer: !process.env.CI,
     env: {
       NUXT_PUBLIC_COMING_SOON: "false",