Answer "what can I press" in one keypress

The Shortcuts settings page answers "how do I change this", which is
worth opening a window for. This answers the other question, the one
you have with your hands already on the keyboard, so it is an overlay
on SUPER + / and the same key closes it.

It reads Keybinds.grouped() rather than a written-down list, so a
shortcut rebound in Settings shows its new chord here with nothing kept
in sync. A cheatsheet that lies is worse than none: it gets consulted
exactly when somebody does not already know.

Three columns, balanced by how many shortcuts each category holds. The
first attempt used a Flow, which wraps into as many columns as it likes
and made 120 binds across six uneven categories unreadable; it also
sized the card from a child that filled it, which is a circular binding
and produced a card taller than the display with its contents running
off the bottom. Both were found by looking at it rather than by a test,
which is the argument for looking at it.

Fixes a real bug on the way past: luaChord and formatChord appended the
key unconditionally, so the window switcher's modifier-only release
bind became "SUPER + " with a dangling separator. That matched neither
the chord keybinds.lua binds nor the one an override is keyed by, so
that bind could never be rebound and had no category -- it was sitting
in a seventh group of its own, which is how it was noticed.

config/dot/quickshell/shell.qml

@@ -34,6 +34,7 @@ import qs.modules.quicksettings
 import qs.modules.notifications
 import qs.modules.capture
 import qs.modules.powermenu
+import qs.modules.cheatsheet
 import qs.modules.clipboard
 import qs.modules.datemenu
 import qs.modules.focus
@@ -98,6 +99,7 @@ ShellRoot {
     QuickSettings { id: quickSettings }
     DateMenu { id: dateMenu }
     ClipboardPanel {}
+    Cheatsheet {}
     CaptureOverlay {}
     IntelligenceResult {}
     ActivityPanel {}
@@ -126,6 +128,24 @@ ShellRoot {
         function cancel(): void { WindowSwitcherState.cancel(); }
     }
 
+    // Every shortcut on one keypress. Toggle so the same chord closes it.
+    IpcHandler {
+        target: "cheatsheet"
+        function toggle(): void { ShellState.toggle("cheatsheet"); }
+        function open(): void { ShellState.open("cheatsheet"); }
+        function close(): void { ShellState.close(); }
+        function status(): string {
+            return JSON.stringify({
+                open: ShellState.cheatsheetOpen,
+                groups: Keybinds.grouped().map(group => group.name),
+                binds: Keybinds.binds.length,
+                uncategorised: Keybinds.binds
+                    .filter(bind => !Keybinds.categoryManifest[bind.luaChord])
+                    .map(bind => bind.chord)
+            });
+        }
+    }
+
     IpcHandler {
         target: "overview"
         function toggle(): void { ShellState.toggle("overview"); }