refactor(ota): implement polling-based update system and fix API typo

- Fix typo in OTA update status API endpoint (/ota_udpate_status → /ota_update_status)
- Replace WebSocket-based update progress with polling mechanism
- Add OTA lifecycle callbacks (started, finished, progress, error)
- Implement check_update_task with internet connectivity verification
- Add LittleFS/SPIFFS update support
- Simplify update progress page to use 90-second delay and polling instead of real-time WebSocket updates

This refactor improves reliability by checking internet connectivity before attempting updates and simplifies the frontend by removing WebSocket complexity in favor of a timeout-based polling approach.

data/logic.js

@@ -49,7 +49,7 @@ function fetchWaterData(gauge) {
 }
 
 function fetchUpdateData(gauge) {
-    const apiUrl = '/ota_udpate_status';
+    const apiUrl = '/ota_update_status';
     // Fetching data from the API
     fetch(apiUrl)
         .then(response => response.json())

data/update_progress.html

@@ -15,44 +15,32 @@
             </div>
         </div>
     </div>
-</body>
 
-<script>
-    const webSocket = new WebSocket('webSocket://' + window.location.host + '/webSocket');
+    <script>
+        // Wait 90 seconds after page load, then start checking if server is up
+        window.addEventListener('load', function() {
+            setTimeout(checkServerAndRedirect, 90000); // 90 seconds = 90000 ms
+        });
 
-    webSocket.onopen = function() {
-      console.log('WebSocket connection opened.');
-    };
-
-    webSocket.onmessage = function(event) {
-      console.log('Progress:', event.data);
-      // Update the progress bar
-      let progress = parseInt(event.data);
-      if (progress == -1) {
-        document.getElementById('progress').textContent = "Upgrade Done, wait for reboot...";
-
-        const checkStatus = setInterval(() => {
-          fetch('/ota_udpate_status')
-            .then(response => {
-              if (response.ok) {
-                clearInterval(checkStatus);
-                window.location.href = '/';
-              }
+        function checkServerAndRedirect() {
+            // Try to fetch the home page to check if server is up
+            fetch('/', {
+                method: 'GET',
+                cache: 'no-cache'
             })
-            .catch(error => console.error('Error checking OTA update status:', error));
-        }, 1000);
-      } else {
-        document.getElementById('progress').textContent = progress + '%';
-      } 
-      
-
-    };
-
-    webSocket.onerror = function(error) {
-      console.error('WebSocket error:', error);
-    };
-
-    webSocket.onclose = function() {
-      console.log('WebSocket connection closed.');
-    };
-  </script>
+            .then(response => {
+                // If we get a response (server is up), redirect to home page
+                if (response.ok) {
+                    window.location.href = '/';
+                } else {
+                    // Server responded but with an error, wait and retry
+                    setTimeout(checkServerAndRedirect, 5000); // 5 seconds = 5000 ms
+                }
+            })
+            .catch(error => {
+                // Fetch failed (server not up yet), wait and retry
+                setTimeout(checkServerAndRedirect, 5000); // 5 seconds = 5000 ms
+            });
+        }
+    </script>
+</body>