Smooth Search Experience

### Problem
Every time a user wants to search, the app navigates to another fragment, leading to an actual network call for each keyboard tap.

https://github.com/nextcloud/android/assets/67455295/28bcb675-b685-4009-ab1f-1cb6750194bc

### Solution
To optimize the search functionality, there's no need to navigate to a different fragment. Instead, we can utilize OCFileListFragment for searching.

As the user starts typing, we can locally filter all files. When the user taps the search button, we can then perform the actual search or we can still make actual network call for each keyboard tap.

We can choose one of these option for provide more better experience for users.

@tobiasKaminsky @AndyScherzinger