chore: remove unused code and suppress noisy Claude Code logs

- Delete unused files: retry.js, app-init.js, model-manager.js
- Remove duplicate error helpers from helpers.js (exist in errors.js)
- Remove unused exports from signature-cache.js, logger.js
- Remove unused frontend code: ErrorHandler methods, validators, canDelete, destroy
- Make internal functions private in thinking-utils.js
- Remove commented-out code from constants.js
- Remove deprecated .glass-panel CSS class
- Add silent handler for Claude Code event logging (/api/event_logging/batch)
- Suppress logging for /v1/messages/count_tokens (501 responses)
- Fix catch-all to use originalUrl (wildcard strips req.path)

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

public/js/utils/error-handler.js

@@ -46,39 +46,6 @@ window.ErrorHandler.safeAsync = async function(fn, errorMessage = null, options
     }
 };
 
-/**
- * Wrap a component method with error handling
- * @param {Function} method - Method to wrap
- * @param {string} errorMessage - Error message prefix
- * @returns {Function} Wrapped method
- */
-window.ErrorHandler.wrapMethod = function(method, errorMessage = null) {
-    return async function(...args) {
-        return window.ErrorHandler.safeAsync(
-            () => method.apply(this, args),
-            errorMessage || Alpine.store('global').t('operationFailed')
-        );
-    };
-};
-
-/**
- * Show a success toast notification
- * @param {string} message - Success message
- */
-window.ErrorHandler.showSuccess = function(message) {
-    const store = Alpine.store('global');
-    store.showToast(message, 'success');
-};
-
-/**
- * Show an info toast notification
- * @param {string} message - Info message
- */
-window.ErrorHandler.showInfo = function(message) {
-    const store = Alpine.store('global');
-    store.showToast(message, 'info');
-};
-
 /**
  * Show an error toast notification
  * @param {string} message - Error message
@@ -90,23 +57,6 @@ window.ErrorHandler.showError = function(message, error = null) {
     store.showToast(fullMessage, 'error');
 };
 
-/**
- * Validate and execute an API call with error handling
- * @param {Function} apiCall - Async function that makes the API call
- * @param {string} successMessage - Message to show on success (optional)
- * @param {string} errorMessage - Message to show on error
- * @returns {Promise<any>} API response or undefined on error
- */
-window.ErrorHandler.apiCall = async function(apiCall, successMessage = null, errorMessage = 'API call failed') {
-    const result = await window.ErrorHandler.safeAsync(apiCall, errorMessage);
-
-    if (result !== undefined && successMessage) {
-        window.ErrorHandler.showSuccess(successMessage);
-    }
-
-    return result;
-};
-
 /**
  * Execute an async function with automatic loading state management
  * @param {Function} asyncFn - Async function to execute