MangoHud 0.7.0 and preset.conf (with Bottles software)

In the new 0.7.0 version, there's a [new feature where user can customize the presets](https://github.com/flightlessmango/MangoHud/releases/tag/v0.7.0) with a `preset.conf` file (or a `presets.conf` (plural!), like the [example file in the MangoHud repo](https://github.com/flightlessmango/MangoHud/blob/master/data/presets.conf).. dunno which is correct).

I'm using Flatpak MangoHud with Bottles software, and by default, the `MangoHud.conf` file is only read from these locations (in this order):

~/.var/app/com.usebottles.bottles/
- config/MangoHud/wine-[program].conf
e.g.
- config/MangoHud/wine-explorer.conf
- config/MangoHud/wine-GAMENAME.conf
- data/bottles/runners/[runner]/bin/MangoHud.conf
e.g.
- data/bottles/runners/soda-7.0-9/bin/MangoHud.conf
- config/MangoHud/wine64-preloader.conf
- config/MangoHud/MangoHud.conf

I've tried to make Flatpak overrides for Bottles to read from `~/.config/MangoHud/` but hasn't been able to make it work.

I also tried to add a "preset(s?).conf" file to all kinds of folders but it doesn't seem to be read at all.

Is this a Bottles or Flatpak MangoHud problem? Thanks!

Start by comparing the MangoHud 0.7.0 release notes and the linked example data/presets.conf with the listed Bottles configuration paths. Reproduce the preset lookup behavior in the Flatpak Bottles setup and determine whether the missing file support belongs to MangoHud, the Flatpak sandbox, or Bottles; document the confirmed configuration and expected behavior when done.

Written by the indexing model from the issue text.