Public page SEO and production analytics (#125)

## Summary
- Closes the public-page gaps from #124: each route gets its own title, description, canonical, heading, links, and JSON-LD, and unknown URLs have a real 404 document.
- Adds HeyCatch and the Google tag (`G-V12DLRLPWR`) only on the production site and the iOS and Android apps. Tianji still loads on beta.
- Needs the server-infra change that stops serving the app shell for missing paths.

## Test plan
- [ ] Build production and confirm `/` and `/pricing/` HTML include a unique title, description, canonical, one h1, social tags, related links, and Organization JSON-LD.
- [ ] Confirm a nonsense path is served as `404.html` once the nginx change is deployed.
- [ ] Confirm beta and local web do not load HeyCatch or gtag, and that a production or native build does.
- [ ] Open the live site after deploy and click around, then mark HeyCatch installed in its dashboard.

Reviewed-on: #125

llm-fe/package.json

@@ -11,10 +11,10 @@
     "@capacitor/keyboard": "^7.0.6",
     "@capacitor/preferences": "^7.0.4",
     "@capacitor/status-bar": "^7.0.6",
-    "native-store-billing": "file:plugins/native-store-billing",
     "@emotion/cache": "^11.14.0",
     "@emotion/react": "^11.14.0",
     "@emotion/styled": "^11.14.0",
+    "@heycatch/sdk": "^0.8.3",
     "@mui/icons-material": "^5.16.11",
     "@mui/material": "^5.16.11",
     "@testing-library/jest-dom": "^6.6.3",
@@ -34,6 +34,7 @@
     "lodash": "^4.17.21",
     "markdown-to-jsx": "^7.7.2",
     "mini.css": "^3.0.1",
+    "native-store-billing": "file:plugins/native-store-billing",
     "papaparse": "^5.5.4",
     "pdfmake": "^0.3.11",
     "react-bootstrap": "^2.10.6",
@@ -53,9 +54,9 @@
   },
   "scripts": {
     "start": "NODE_ENV=development react-scripts start",
-    "build": "NODE_ENV=production react-scripts build",
-    "build:prod": "NODE_ENV=production react-scripts build && mkdir -p /var/www/prod.chat.aimloperations/html && cp -r ./build/* /var/www/prod.chat.aimloperations/html/",
-    "build:beta": "bash -c 'set -a; source .env.beta; set +a; NODE_ENV=production react-scripts build' && mkdir -p /var/www/beta.chat.aimloperations/html && cp -r ./build/* /var/www/beta.chat.aimloperations/html/",
+    "build": "node scripts/writeSitemap.js && NODE_ENV=production react-scripts build && node scripts/stampCanonicals.js",
+    "build:prod": "node scripts/writeSitemap.js && NODE_ENV=production react-scripts build && node scripts/stampCanonicals.js && mkdir -p /var/www/prod.chat.aimloperations/html && cp -r ./build/* /var/www/prod.chat.aimloperations/html/ && node scripts/pingIndexNow.js",
+    "build:beta": "node scripts/writeSitemap.js && bash -c 'set -a; source .env.beta; set +a; NODE_ENV=production react-scripts build' && node scripts/stampCanonicals.js && mkdir -p /var/www/beta.chat.aimloperations/html && cp -r ./build/* /var/www/beta.chat.aimloperations/html/",
     "build:mobile": "bash -c 'set -a; source .env.mobile; set +a; NODE_ENV=production react-scripts build' && npx cap sync",
     "android:open": "npx cap open android",
     "android:sync": "npx cap sync android",
@@ -63,7 +64,7 @@
     "ios:sync": "npx cap sync ios",
     "assets:generate": "npx capacitor-assets generate --ios --android",
     "test": "NODE_ENV=development react-scripts test",
-    "test:ci": "CI=true NODE_ENV=development react-scripts test --watchAll=false --coverage=false",
+    "test:ci": "CI=true NODE_ENV=development react-scripts test --watchAll=false --coverage=false && node --test scripts/stampCanonicals.test.js scripts/sitemap.test.js",
     "eject": "react-scripts eject"
   },
   "eslintConfig": {