feat: typed script parameters with validation and icon-grid selector

- Add ScriptParameterConfig model (string, integer, float, boolean, select types)
- Server-side validation at both define-time and execute-time
- Parameters passed as SCRIPT_PARAM_* environment variables
- Web UI parameter editor in script create/edit dialog (add/remove/reorder)
- Icon-grid selector component (ported from wled-screen-controller)
- Replace audio device dropdown with icon-grid selector
- Replace callback event dropdown with icon-grid selector
- Localization for parameter UI (en, ru)

media_server/static/index.html

@@ -465,6 +465,14 @@
                     <span data-i18n="scripts.field.timeout">Timeout (seconds)</span>
                     <input type="number" id="scriptTimeout" value="30" min="1" max="300">
                 </label>
+
+                <div class="params-section">
+                    <div class="params-header">
+                        <span data-i18n="scripts.field.parameters">Parameters</span>
+                        <button type="button" class="btn-small" onclick="addParameterRow()" data-i18n="scripts.params.add">+ Add</button>
+                    </div>
+                    <div id="scriptParamsContainer"></div>
+                </div>
             </div>
             <div class="dialog-footer">
                 <button type="button" class="btn-secondary" onclick="closeScriptDialog()" data-i18n="scripts.button.cancel">Cancel</button>
@@ -473,6 +481,22 @@
         </form>
     </dialog>
 
+    <!-- Script Parameters Input Dialog (shown before executing scripts with params) -->
+    <dialog id="scriptParamsDialog">
+        <div class="dialog-header">
+            <h3 id="scriptParamsDialogTitle">Execute Script</h3>
+        </div>
+        <form id="scriptParamsForm" onsubmit="submitScriptWithParams(event)">
+            <div class="dialog-body">
+                <div id="scriptParamsInputs"></div>
+            </div>
+            <div class="dialog-footer">
+                <button type="button" class="btn-secondary" onclick="closeScriptParamsDialog()" data-i18n="scripts.button.cancel">Cancel</button>
+                <button type="submit" class="btn-primary" data-i18n="scripts.params.execute">Execute</button>
+            </div>
+        </form>
+    </dialog>
+
     <!-- Add/Edit Callback Dialog -->
     <dialog id="callbackDialog">
         <div class="dialog-header">