Implement local filtering in file list

[juliushaertl]

Bring back local file list filtering which got removed with the implementation of unified search. It additionally introduces a bundled entrypoint for the files app which now unifies search handling, templates and the files app settings in the left navigation sidebar.

[nickvergessen]

There is no indication once the unified search is closed that the file list is filtered

So in theory there is, but it might not be as visible as it used to be

[nickvergessen]

Fixed the problem with the broken "No entries in this folder" message

Before	After

[nickvergessen]

Switching between file lists might need to be handled with special care so that the search query gets updated on all file lists

So yeah, it doesn't work fully, but it is better than on 19. On 19 the search box is emptied and visible but the filter is still applied, giving you even more headache :P

From my POV this is already a huge step forward and should be merged + backported.
Fixing the filter to work completely across pages in all cases can be done later

[PVince81]

Fixes #23432

[juliushaertl]

I'll be leaving the follow up points for later as I agree with @nickvergessen that this is already a huge step forward and the old implementation had similar flaws when switching the file list:

• There is no indication once the unified search is closed that the file list is filtered
• Switching between file lists might need to be handled with special care so that the search query gets updated on all file lists

[juliushaertl]

Diff in case it might be useful to make sure that newly initialized filelists also have the filter, but there are some sideeffects when it comes to the loading indicator:

 import { subscribe } from '@nextcloud/event-bus'
 
+let searchQuery = ''
+subscribe('nextcloud:unified-search.search', ({ query }) => {
+       searchQuery = query ?? ''
+});
+
 (function() {
 
        const FilesPlugin = {
                attach(fileList) {
+                       // Initialize the file list with the current query in case there was a search before switching to the list
+                       fileList.setFilter(searchQuery)
+
                        subscribe('nextcloud:unified-search.search', ({ query }) => {
                                fileList.setFilter(query)
                        })

[juliushaertl]

/backport to stable22

[juliushaertl]

/backport to stable21

[juliushaertl]

/backport to stable20

[Pytal]

👌

[PVince81]

Tested, works 👍

It's only strange that the dropdown also shows the same results after a while, but no biggie

[backportbot-nextcloud]

The backport to stable22 failed. Please do this backport manually.

[backportbot-nextcloud]

The backport to stable21 failed. Please do this backport manually.

[backportbot-nextcloud]

The backport to stable20 failed. Please do this backport manually.