feat(chat): implement initial chatbot UI and functionality

This commit introduces the foundational user-facing chatbot interface.

- Adds a new `ChatbotPage` component with a complete UI for displaying messages, user input, and a simulated bot response.
- Implements a "typing" indicator for a better user experience.
- Integrates `react-router-dom` to handle application routing, directing the root path to the new chatbot and moving the admin login to `/admin`.
- Adds `react-icons` as a new dependency for UI elements.
- Extends Tailwind CSS theme with new colors and adds custom CSS for the typing animation.

adventure-rental-app/package-lock.json

@@ -11,6 +11,7 @@
         "axios": "^1.11.0",
         "react": "^19.1.0",
         "react-dom": "^19.1.0",
+        "react-icons": "^5.5.0",
         "react-router-dom": "^7.7.1"
       },
       "devDependencies": {
@@ -3580,6 +3581,15 @@
         "react": "^19.1.1"
       }
     },
+    "node_modules/react-icons": {
+      "version": "5.5.0",
+      "resolved": "https://registry.npmjs.org/react-icons/-/react-icons-5.5.0.tgz",
+      "integrity": "sha512-MEFcXdkP3dLo8uumGI5xN3lDFNsRtrjbOEKDLD7yv76v4wpnEq2Lt2qeHaQOr34I/wPN3s3+N08WkQ+CW37Xiw==",
+      "license": "MIT",
+      "peerDependencies": {
+        "react": "*"
+      }
+    },
     "node_modules/react-refresh": {
       "version": "0.17.0",
       "resolved": "https://registry.npmjs.org/react-refresh/-/react-refresh-0.17.0.tgz",