Release 2.12.0

ABI summary:

• No ABI changes

Enhancements:

• [Wayland] Implement wp_primary_selection_unstable_v1 (Fixes #2699, Fixes #2583)
• [platform] Add DRMFormat::as_mir_format()
• [Wayland] Manually implement wl_shm/wl_shm_pool. (Closes: #2669)

Bugs fixed:

• [miral] InternalClient don't use a dead wl_display (Fixes: #2344)
• [input] Move XKB modifier tracking from Wayland frontend to KeyMapper. (Fixes #2720, Fixes #2145)
• [gbm-kms] Ensure that a candidate device has the hardware to support at least one physical display. (Fixes: #2258)
• Fix overlapping outputs of different scale. (Fixes: #2758)
• After idle timeout the powermode change needs to be applied to the base display configuration. (Fixes: #2757, Fixes: #2695)
• [Xwayland] Do not abort when nothing is wrong. (Fixes: #2790)