fix(ui): restore trigger character suggestions + fix overflow

- Re-enable suggestOnTriggerCharacters so typing " triggers property suggestions
- Re-add fixedOverflowWidgets to prevent suggest widget clipping at editor top
- Keep quickSuggestions disabled to prevent "No suggestions" popup while typing
- contentJustChanged only flags small single-char edits (not setValue/reformat)

Author: lan17

ui/src/core/page-components/agent-detail/modals/edit-control/json-editor-view.tsx

@@ -75,7 +75,7 @@ const EDITOR_OPTIONS: import('monaco-editor').editor.IStandaloneEditorConstructi
   {
     automaticLayout: true,
     quickSuggestions: false,
-    suggestOnTriggerCharacters: false,
+    suggestOnTriggerCharacters: true,
     wordBasedSuggestions: 'off',
     suggest: {
       showWords: false,
@@ -94,6 +94,7 @@ const EDITOR_OPTIONS: import('monaco-editor').editor.IStandaloneEditorConstructi
     tabSize: 2,
     insertSpaces: true,
     wordWrap: 'off',
+    fixedOverflowWidgets: true,
     bracketPairColorization: { enabled: true },
     guides: { bracketPairs: true, indentation: true },
     stickyScroll: { enabled: true },