Remove dead code from profile and password proxy systems

Strip ~966 lines of unused code after transitioning to cookie-only
auth: profile CRUD handlers, encryption helpers, username/password
proxy launcher, proxy check/version handlers, dead preload methods,
orphaned CSS (modals, profiles, nav tabs, collapsible sections),
unused DOM elements and renderer functions.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

preload.js

@@ -3,24 +3,12 @@ const { contextBridge, ipcRenderer } = require('electron');
 // Expose protected methods that allow the renderer process to use
 // the ipcRenderer without exposing the entire object
 contextBridge.exposeInMainWorld('electronAPI', {
-  login: (credentials) => ipcRenderer.invoke('api-login', credentials),
   getDevices: (params) => ipcRenderer.invoke('api-get-devices', params),
   getAuthInfo: (params) => ipcRenderer.invoke('api-get-auth-info', params),
-  
-  // Profile management
-  loadProfiles: () => ipcRenderer.invoke('profiles-load'),
-  saveProfile: (profile) => ipcRenderer.invoke('profiles-save', profile),
-  getProfile: (profileId) => ipcRenderer.invoke('profiles-get', { profileId }),
-  deleteProfile: (profileId) => ipcRenderer.invoke('profiles-delete', { profileId }),
-  updateProfile: (profileId, profile) => ipcRenderer.invoke('profiles-update', { profileId, ...profile }),
-  
+
   // Camera proxy functionality
-  launchCameraProxy: (params) => ipcRenderer.invoke('camera-proxy-launch', params),
   launchCookieCameraProxy: (params) => ipcRenderer.invoke('camera-proxy-cookie-launch', params),
   stopCameraProxy: (processId) => ipcRenderer.invoke('camera-proxy-stop', { processId }),
-  checkCameraProxy: () => ipcRenderer.invoke('camera-proxy-check'),
-  getCameraProxyVersion: () => ipcRenderer.invoke('camera-proxy-version'),
-  listActiveCameraProxies: () => ipcRenderer.invoke('camera-proxy-list-active'),
 
   // Extension cookie bridge (push from main process)
   onExtensionCookie: (callback) => {