Refactor: Complete codebase reorganization and modernization

- Split server.js routes into modular files (server/routes/)
  - departures.js: Departure data endpoints
  - sites.js: Site search and nearby sites
  - config.js: Configuration endpoints

- Reorganized file structure following Node.js best practices:
  - Moved sites-config.json to config/sites.json
  - Moved API_RESPONSE_DOCUMENTATION.md to docs/
  - Moved raspberry-pi-setup.sh to scripts/
  - Archived legacy files to archive/ directory

- Updated all code references to new file locations
- Added archive/ to .gitignore to exclude legacy files from repo
- Updated README.md with new structure and organization
- All functionality tested and working correctly

Version: 1.2.0

config/sites.json

@@ -0,0 +1,29 @@
+{
+  "orientation": "normal",
+  "darkMode": "auto",
+  "backgroundImage": "https://images.unsplash.com/photo-1509356843151-3e7d96241e11?q=80&w=1000",
+  "backgroundOpacity": 0.45,
+  "sites": [
+    {
+      "id": "1411",
+      "name": "Ambassaderna",
+      "enabled": true
+    },
+    {
+      "id": "1410",
+      "name": "Berwaldhallen",
+      "enabled": true
+    },
+    {
+      "id": "1100",
+      "name": "Djurgårdsbron",
+      "enabled": true
+    },
+    {
+      "id": "1110",
+      "name": "Radiohuset",
+      "enabled": true
+    }
+  ],
+  "combineSameDirection": true
+}