feat(dotfiles): zz-blankpad host override package

Host-specific divergence for blankpad deployed last with override semantics:
display layout (its own outputs, not Dankware's DP/eDP rig), autostart and
keybinds targeting the bare 'noctalia' CLI instead of qs -c noctalia-shell,
misc without renderD129, rules without the Noctalia floating-window rule, and
blank's own .zshrc. All other packages deploy canonical from base.

dotfiles/zz-blankpad/niri/.config/niri/cfg/misc.kdl

@@ -0,0 +1,32 @@
+    prefer-no-csd
+    screenshot-path null
+
+    environment {
+        ELECTRON_OZONE_PLATFORM_HINT "auto"
+        QT_QPA_PLATFORM "wayland"
+        QT_QPA_PLATFORMTHEME "gtk3"
+        QT_WAYLAND_DISABLE_WINDOWDECORATION "1"
+        XDG_CURRENT_DESKTOP "niri"
+        XDG_SESSION_TYPE "wayland"
+    }
+
+    cursor {
+        xcursor-theme "capitaine-cursors"
+        xcursor-size 24
+    }
+
+    blur {
+        passes 2        // more passes = stronger blur (default: 3)
+        offset 3.0      // sample distance per pass (default: 3.0)
+        noise 0.03      // grain overlay (default: 0.02)
+        saturation 1.0  // color saturation boost (default: 1.5)
+    }
+
+    debug {
+        // Allows notification actions and window activation from Noctalia.
+        honor-xdg-activation-with-invalid-serial
+    }
+
+    hotkey-overlay {
+       skip-at-startup
+    }