refactor: Remove CORS proxy code (not needed for same-domain setup)

- Remove NEXTCLOUD_PROXY constant
- Remove fetchWithProxy() and getProxiedUrl() methods
- Remove useProxy flag from NextcloudStorage
- Keep window.app onclick handlers for dynamically generated buttons
- Clean up code since Nextcloud and TeeTracker run on same domain (wralto.org)

Co-authored-by: trevor1969 <trevor1969@users.noreply.github.com>

app.js

@@ -12,9 +12,6 @@ const STORAGE_KEY_NC_CONFIG = 'teatracker_nextcloud_config';
 // Nextcloud Storage Integration
 // ============================================
 
-// CORS Proxy for Nextcloud WebDAV (fallback when direct connection fails due to CORS)
-const NEXTCLOUD_PROXY = 'https://corsproxy.io/?';
-
 class NextcloudStorage {
     constructor(baseUrl, username, password, path = '/TeeTracker/') {
         this.baseUrl = baseUrl.replace(/\/$/, '');
@@ -24,7 +21,6 @@ class NextcloudStorage {
         this.authHeader = 'Basic ' + btoa(`${username}:${password}`);
         this.connected = false;
         this.lastError = null;
-        this.useProxy = false;
     }
 
     getFileUrl(filename) {
@@ -34,54 +30,10 @@ class NextcloudStorage {
     getDirectoryUrl() {
         return `${this.baseUrl}/remote.php/dav/files/${encodeURIComponent(this.username)}${this.path}`;
     }
-    // Get proxied URL for CORS fallback
-    getProxiedUrl(url) {
-        return `${NEXTCLOUD_PROXY}${encodeURIComponent(url)}`;
-    }
-
-    // Wrapper for fetch that automatically uses proxy on CORS failure
-    async fetchWithProxy(url, options = {}) {
-        try {
-            // First try direct connection
-            const response = await fetch(url, options);
-            
-            // If we get a CORS error or network error, it will throw
-            // If we get here, the request succeeded (even if status is not 2xx)
-            if (response.ok || response.status === 404 || response.status === 405) {
-                this.useProxy = false;
-                return response;
-            }
-            
-            // Some errors might still occur, so try proxy
-            console.log('Direct connection returned non-ok status, trying proxy...');
-        } catch (error) {
-            // Direct connection failed (CORS or network error), try proxy
-            console.log('Direct connection failed, trying proxy...');
-        }
-        
-        // Try with proxy
-        try {
-            const proxyUrl = this.getProxiedUrl(url);
-            this.useProxy = true;
-            const response = await fetch(proxyUrl, options);
-            
-            if (response.ok || response.status === 404 || response.status === 405) {
-                console.log('Proxy connection successful');
-                return response;
-            }
-            
-            // If proxy also fails, throw error
-            throw new Error(`Proxy returned status: ${response.status}`);
-        } catch (proxyError) {
-            this.useProxy = false;
-            console.error('Proxy connection also failed:', proxyError);
-            throw new Error(`Both direct and proxy connections failed: ${proxyError.message || ''}`);
-        }
-    }
 
     async testConnection() {
         try {
-            const response = await this.fetchWithProxy(this.getDirectoryUrl(), {
+            const response = await fetch(this.getDirectoryUrl(), {
                 method: 'PROPFIND',
                 headers: {
                     'Authorization': this.authHeader,
@@ -113,7 +65,7 @@ class NextcloudStorage {
 
     async ensureDirectory() {
         try {
-            const response = await this.fetchWithProxy(this.getDirectoryUrl(), {
+            const response = await fetch(this.getDirectoryUrl(), {
                 method: 'MKCOL',
                 headers: { 'Authorization': this.authHeader }
             });
@@ -128,7 +80,7 @@ class NextcloudStorage {
     async ensureSubDirectory(subPath) {
         try {
             const subDirUrl = `${this.getDirectoryUrl()}${subPath}/`;
-            const response = await this.fetchWithProxy(subDirUrl, {
+            const response = await fetch(subDirUrl, {
                 method: 'MKCOL',
                 headers: { 'Authorization': this.authHeader }
             });
@@ -142,7 +94,7 @@ class NextcloudStorage {
     async loadFile(filename) {
         try {
             const url = this.getFileUrl(filename);
-            const response = await this.fetchWithProxy(url, {
+            const response = await fetch(url, {
                 headers: { 'Authorization': this.authHeader }
             });
 
@@ -162,7 +114,7 @@ class NextcloudStorage {
     async saveFile(filename, data) {
         try {
             const url = this.getFileUrl(filename);
-            const response = await this.fetchWithProxy(url, {
+            const response = await fetch(url, {
                 method: 'PUT',
                 headers: {
                     'Authorization': this.authHeader,
@@ -180,7 +132,7 @@ class NextcloudStorage {
     async fileExists(filename) {
         try {
             const url = this.getFileUrl(filename);
-            const response = await this.fetchWithProxy(url, {
+            const response = await fetch(url, {
                 method: 'HEAD',
                 headers: { 'Authorization': this.authHeader }
             });