[libadwaita] (9 commits) Non-fast-forward update to branch wip/exalm/dark

[Alexander Mikhaylenko <alexm src gnome org>]

The branch 'wip/exalm/dark' was changed in a way that was not a fast-forward update.
NOTE: This may cause problems for people pulling from the branch. For more information,
please see:

 https://wiki.gnome.org/Git/Help/NonFastForward

Commits removed from the branch:

  bc21f7a... Add AdwSettings
  b394d76... Add AdwStyleManager
  ba74a33... application: Proxy AdwStyleManager API
  70938bb... demo: Rework the dark mode button
  816e2ff... doc: Mention default color scheme change in migration guide

Commits added to the branch:

  198e559... stylesheet: Fix .osd button states (*)
  e6509c8... Add AdwSettings
  cddadf6... Add AdwStyleManager
  37dfd8d... application: Add style-manager property
  2c0e633... application: Remove gtk-application-prefer-dark-theme menti
  0aa32f4... application: Use AdwStyleManager properties to control styl
  db03957... demo: Rework the dark mode button
  ff660ef... doc: Mention HdyStyleManager in migration guide
  a86b39d... doc: Mention default color scheme change in migration guide

(*) This commit already existed in another branch; no separate mail sent