fix: view_assets form submit — use script bind instead of urlwidget

Remove submit_url + submited/urlwidget pattern (event.params is Response
object, not widget descriptor, causes silent failure).
Replace with submit event + actiontype:script that manually POSTs form
data via fetch() and renders response widget tree via bricks.widgetBuild.

wwwroot/view_assets.ui

@@ -18,7 +18,6 @@
             "widgettype": "Form",
             "id": "view_assets_form",
             "options": {
-                "submit_url": "{{entire_url('api/submit_list_assets.dspy')}}",
                 "fields": [
                     {
                         "uitype": "code",
@@ -35,13 +34,10 @@
             "binds": [
                 {
                     "wid": "self",
-                    "event": "submited",
-                    "actiontype": "urlwidget",
-                    "target": "app.rl_asset_results",
-                    "options": {
-                        "method": "POST"
-                    },
-                    "mode": "replace"
+                    "event": "submit",
+                    "actiontype": "script",
+                    "target": "self",
+                    "script": "(async function(){var form=bricks.getWidgetById('view_assets_form',bricks.app);if(!form)return;var vals=form._getValue();var params=new URLSearchParams();for(var k in vals){if(vals[k]!==undefined&&vals[k]!==null)params.append(k,vals[k])}var url=bricks.app.baseUrl+'/reallife_asset/api/submit_list_assets.dspy?_webbricks_=1';var resp=await fetch(url,{method:'POST',body:params});var desc=await resp.json();var target=bricks.getWidgetById('rl_asset_results',bricks.app);if(!target)return;if(target.destroy_subwidgets)target.destroy_subwidgets();target.subwidgets=[];target.el.innerHTML='';if(desc&&desc.widgettype){await bricks.widgetBuild(desc,target)}})()"
                 }
             ]
         },