When two windows are tiled side-by-side or in complementary quarter-tile
positions, dragging the shared inside edge now resizes both windows
simultaneously.

Fixes #615

When using switch-windows-all to cycle through windows across all
workspaces, marco was grouping windows by workspace rather than using
a global MRU (most-recently-used) list. This caused several issues:

- Sticky windows appeared multiple times, once per workspace
- Window order was confusing (since they were grouped by workspace number)
- Behavior was different from other window managers

Fixed by collecting all windows, sorting them by recency, then building
the tab list from this global list.

Fixes #286

pass focus to window if it is on another workspace

Corner-tiled windows were being treated as maximized horizontally, which
is wrong. Instead, we clear all maximized flags to make sure their size
is respected on reload.

Fixes #710

Bumps [actions/cache](https://github.com/actions/cache) from 4 to 5.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](https://github.com/actions/cache/compare/v4...v5)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-version: '5'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Bumps [actions/checkout](https://github.com/actions/checkout) from 5 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](https://github.com/actions/checkout/compare/v5...v6)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Add Shift+Print keybinding to trigger 'mate-screenshot --area' for
interactive area selection. This gives users a dedicated keybinding for
area screenshots in addition to the existing Print (screen) and
Alt+Print (window) shortcuts.

Fixes mate-desktop/marco#157

This prevents race conditions with applications like mate-screenshot
that need to grab input (e.g. for area selection).

Fixes mate-desktop/mate-utils#37

Replace putenv-based child setup with glib environment functions. This
enables posix_spawn for keybindings and it fixes an old memory leak with
not being able to free the string we added to putenv.

There was a 10px difference in the calculation between the (correct)
center-new-windows placement and the (incorrect) move-to-center
keybinding. By using the same function in both places we can make sure
the calculation is consistent.