fix: Promise rendering in flows view addFooter

Fixed "[object Promise]" display bug in the flows view.

## Problem:
- Flows view was showing "[object Promise]" text on the page
- Root cause: The `addFooter()` function was returning a Promise
- LuCI calls `addFooter()` synchronously and expects it to return nothing or DOM elements
- When a Promise is returned, LuCI tries to render it as text, showing "[object Promise]"

## Solution:
Changed from:
```javascript
addFooter: function() {
    return Promise.all([...]).then(...);
}
```

To:
```javascript
addFooter: function() {
    Promise.all([...]).then(...);  // Execute but don't return
}
```

## Technical Details:
- The `addFooter()` hook is called after `render()` for post-render initialization
- It should perform async operations but not return promises
- The promise still executes and populates the containers correctly
- Only the return value was changed (removed the `return` keyword)

## Testing:
- Deployed to router
- Flows view now displays correctly without "[object Promise]"
- Initial data loading works properly
- Polling continues to update data

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

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

package/secubox/luci-app-secubox-netifyd/htdocs/luci-static/resources/view/secubox-netifyd/flows.js

@@ -383,8 +383,8 @@ return view.extend({
 	},
 
 	addFooter: function() {
-		// Initial render
-		return Promise.all([
+		// Initial render - execute promise but don't return it
+		Promise.all([
 			netifydAPI.getDashboard()
 		]).then(L.bind(function(result) {
 			var dashboard = result[0] || {};