Draw a cursor, handle the lid, and everything a real config needs

Groundwork for actually daily-driving this: porting the user's Hyprland
config exposed what srdwm couldn't yet express, and testing on a bare TTY
exposed something worse.

A visible mouse cursor. Nothing drew a pointer at all - on a bare TTY the
mouse was simply invisible. It hid because the nested backend runs inside
another compositor, which draws a cursor over srdwm's window; only the DRM
backend, i.e. the actual session path, was affected. A built-in arrow is now
composited above everything on the output the pointer is on. It's a
reviewable ASCII bitmap rather than an XCursor theme: a cursor that is always
present beats a prettier one that sometimes isn't, the same reasoning as
decoration.rs's font fallback. Client-set cursor surfaces and named shapes
are still not rendered, so an app asking for an I-beam gets the arrow.

Lid switch. libinput switch events are handled and surfaced to config as
srd.on("lid_closed"/"lid_open", fn), so closing the lid can lock and suspend
instead of doing nothing.

Config-driven additions, each needed by a binding in the ported config and
none of which existed: fullscreen (Window.fullscreen was a dead field --
declared, never read or written), directional window move that swaps with
the neighbour and reorders the stack so tiling follows, focus cycling,
modifier+drag to move/resize anywhere in a window rather than only by the
titlebar, modifier+scroll to change workspace, and 8 XF86 media/power
keysyms taken from the system's own XF86keysym.h. The keysym tables are
hand-maintained in both directions and a key missing from either fails
silently, so a round-trip test now covers every one the configs bind.

Verified in the QEMU VM: a bare-TTY screendump shows a recognisable arrow at
the pointer position (113 white fill + 58 black outline pixels at screen
centre, where the pointer starts).

1 files changed, 23 insertions, 0 deletions

diff --git a/docs/IMPLEMENTATION_STATUS.md b/docs/IMPLEMENTATION_STATUS.md
index 35635c0..6b2579b 100644
--- a/docs/IMPLEMENTATION_STATUS.md
+++ b/docs/IMPLEMENTATION_STATUS.md
@@ -513,6 +513,29 @@ built them:
   `WAYLAND_DEBUG=1` protocol tracing and fixing real bugs - see the
   Wayland backend section above for the full account.
 
+- ✅ **Mouse cursor** (`crates/wayland/src/cursor.rs`). Previously **nothing
+  drew a pointer at all** - invisible mouse on a bare TTY. It hid because
+  the nested backend runs inside another compositor, which draws a cursor
+  over srdwm's window; only the DRM backend is affected, and only when run
+  as a real session. A built-in arrow (a reviewable ASCII bitmap, no XCursor
+  theme dependency, same reasoning as `decoration.rs`'s font fallback) is
+  now composited above everything on the output the pointer is on.
+  `CursorImageStatus::Hidden` is honoured. **Not** yet done: rendering a
+  client's own cursor surface or a named shape, so an app asking for an
+  I-beam still gets the arrow.
+  **Verified in the QEMU VM**: screendump of a bare-TTY session shows a
+  recognisable arrow at the pointer position - 113 white fill + 58 black
+  outline pixels at screen centre, where the pointer starts.
+- ✅ **Lid switch**: libinput switch events are handled and surfaced to
+  config as `srd.on("lid_closed"/"lid_open", fn)`, so a session can lock and
+  suspend on lid close. Previously there was no switch handling at all.
+- ✅ **Fullscreen** (`srd.window.fullscreen()`), **directional window move**
+  (`srd.window.move("left")`, swaps with the neighbour), **focus cycling**
+  (`srd.window.next()`/`prev()`), **modifier+drag move/resize anywhere in a
+  window**, **modifier+scroll workspace switching**, and 8 more `XF86`
+  media/power keysyms. All were needed to port a real Hyprland config and
+  none existed before.
+
 ## Not implemented anywhere yet
 
 All three protocols originally identified as blocking srdwm-wayland from