feat: add shared utilities and table macros

- Add shared table macros for consistent table styling
- Add shared JavaScript utilities (date formatting, etc.)
- Add admin settings API enhancements
- Add admin schema updates

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

static/shared/js/utils.js

@@ -184,7 +184,86 @@ const Utils = {
     }
 };
 
+// ============================================================================
+// Platform Settings
+// ============================================================================
+
+/**
+ * Platform settings cache and loader
+ */
+const PlatformSettings = {
+    _settings: null,
+    _loading: false,
+    _loadPromise: null,
+
+    /**
+     * Load platform display settings from API
+     * @returns {Promise<Object>} Platform settings
+     */
+    async load() {
+        // Return cached settings if available
+        if (this._settings) {
+            return this._settings;
+        }
+
+        // Return existing promise if already loading
+        if (this._loadPromise) {
+            return this._loadPromise;
+        }
+
+        this._loading = true;
+        this._loadPromise = (async () => {
+            try {
+                const response = await fetch('/api/v1/admin/settings/display/public');
+                if (response.ok) {
+                    this._settings = await response.json();
+                } else {
+                    // Default settings
+                    this._settings = { rows_per_page: 20 };
+                }
+            } catch (error) {
+                console.warn('Failed to load platform settings, using defaults:', error);
+                this._settings = { rows_per_page: 20 };
+            }
+            this._loading = false;
+            return this._settings;
+        })();
+
+        return this._loadPromise;
+    },
+
+    /**
+     * Get rows per page setting
+     * @returns {number} Rows per page (default: 20)
+     */
+    getRowsPerPage() {
+        return this._settings?.rows_per_page || 20;
+    },
+
+    /**
+     * Get rows per page synchronously (returns cached or default)
+     * @returns {number} Rows per page
+     */
+    get rowsPerPage() {
+        return this._settings?.rows_per_page || 20;
+    },
+
+    /**
+     * Reset cached settings (call after updating settings)
+     */
+    reset() {
+        this._settings = null;
+        this._loadPromise = null;
+    }
+};
+
+// Load settings on page load
+document.addEventListener('DOMContentLoaded', () => {
+    PlatformSettings.load();
+});
+
 // Make available globally
+window.PlatformSettings = PlatformSettings;
 window.Utils = Utils;
 
 // Export for modules