feat(config): adjust workspace layout toggle defaults and add window centering command

dot_config/hypr/looknfeel.lua

@@ -120,10 +120,20 @@ hl.animation({ leaf = "borderangle", enabled = true, speed = 100, bezier = "line
 --   },
 -- })
 
--- https://wiki.hypr.land/Configuring/Layouts/Scrolling-Layout/
--- hl.config({
---   scrolling = {
---     -- See only one column per screen instead of two.
---     column_width = 0.97,
---   },
--- })
+-- Scrolling layout, matched to niri's layout block
+-- (~/.config/niri/config.d/20-layout-and-overview.kdl). Wins over Omarchy's
+-- column_width = 0.49.
+hl.config({
+  scrolling = {
+    -- default-column-width { proportion 0.5; }
+    column_width = 0.5,
+    -- preset-column-widths; SUPER + R / SUPER + SHIFT + R cycle these
+    -- (colresize +conf / -conf via omarchy-cycle-window-size).
+    explicit_column_widths = "0.333, 0.5, 0.667",
+    -- center-focused-column "never": scroll only as far as needed to fit the
+    -- focused column. SUPER + C centers on demand.
+    focus_fit_method = 1,
+    -- niri keeps a lone column at its own width instead of filling the screen.
+    fullscreen_on_one_column = false,
+  },
+})