niri: add page (#22534)

Co-authored-by: Lena Pastwa <lena@lnps.me>

pages/linux/niri.md

@@ -0,0 +1,32 @@
+# niri
+
+> A scrollable-tiling Wayland compositor.
+> More information: <https://github.com/YaLTeR/niri>.
+
+- List all outputs and their properties:
+
+`niri msg outputs`
+
+- Turn off an output (monitor):
+
+`niri msg output {{output_name}} off`
+
+- Focus the workspace below the current one:
+
+`niri msg action focus-workspace-down`
+
+- Focus the workspace above the current one:
+
+`niri msg action focus-workspace-up`
+
+- Move the current workspace down:
+
+`niri msg action move-workspace-down`
+
+- Close the currently focused window:
+
+`niri msg action close-window`
+
+- Focus a specific workspace by index:
+
+`niri msg action focus-workspace {{workspace_index}}`