window/wayland: Replace constraint side effect peeking with state checks

When the MetaWindow resize machinery for toplevels ended up in the
Wayland window implementation, we tried to avoid configuring
not-yet-mapped windows that just had its zero sized dimension pass
through the constraint machinery, resulting in a 1x1 sized window.

If we'd properly set up the min size metadata earlier, that 1x1 would
likely be the minimum size set of a window, which makes things harder to
predict when peeking at side effects.

However, what the side effect peeking intends to do, as documented in
the comment, was to figure out when the client hadn't committed any
buffer yet, i.e. during the initial map, and in those cases avoid
sending that nasty 1x1 size, resulting in silly window sizes. A more
robust way to detect this is instead checking when we shouldn't really
try resize things our own way, and in those cases early out as was done
before.

This means that, for a yet to me mapped window, we only ever want to
send an initial non-zero configuration when 1) it's initially maximized,
2) initially fullscreen, or 3) initially tiled in any way, as those are
the situations where the compositor is the one deciding the size.

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Also adds a test for checking initial maximized window sizes.