theme: soften the YoRHa shapes; SUPER+D opens the dashboard

The square markers, block meters and hard-cornered fills read as boxy
next to the porthole. The desktop is now soft throughout: the porthole
is the shape everything is built around and every smaller surface echoes
it.

- Theme gains radiusS / radiusM / radiusL. radiusL is frameRadius - padS,
  so anything inset padS inside one of the frame's curves is concentric
  with it.
- P5Panel and Skew draw rounded rectangles (Geom.roundedRect) whenever
  they neither lean nor are chopped, which is always now; the polygon
  path is kept for shapes brought back on purpose.
- Markers are dots; workspace pips, toggles, transport and media chips,
  notification actions and today's date are pills or discs; the slider
  handle is round. Meters are one continuous rounded line that glides to
  its level instead of a row of segments.
- Album art is rounded with ClippingRectangle in the bar, the media
  popout and the dashboard.
- Free-standing panels (launcher, ask) drop the corner brackets and take
  the frame radius.
- Fix: a hovered notification's wash was a full-bleed square, so in the
  drawer's bottom corner it ran past the drawer's curve. It is inset by
  padS/2 and rounded by radiusL, which keeps it inside the curve.

Hyprland: the discord special workspace and its window rule are gone,
SUPER+S stays the only scratchpad, and SUPER+D now opens the dashboard
(it was on SUPER+I).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

quickshell/bar/MediaPill.qml

@@ -2,6 +2,7 @@ import QtQuick
 import QtQuick.Shapes
 import QtQuick.Window
 import Quickshell
+import Quickshell.Widgets
 import "root:/config"
 import "root:/components"
 import "root:/services"
@@ -41,12 +42,13 @@ BarPill {
         anchors.left: parent.left
         spacing: Theme.padS
 
-        // Album art in a hairline frame.
-        Rectangle {
+        // Album art, rounded, in a hairline frame.
+        ClippingRectangle {
             id: artFrame
             anchors.verticalCenter: parent.verticalCenter
             width: 24
             height: 24
+            radius: Theme.radiusS
             color: Theme.surface
             border.width: 1
             border.color: Theme.overlay
@@ -111,9 +113,9 @@ BarPill {
             }
         }
 
-        // Signal meter: five hairline bars, NieR's audio readout rather than a
+        // Signal meter: five thin rounded bars, NieR's audio readout rather than a
         // chunky equaliser. It moves only while audio is playing and settles
-        // into a row of square dots when paused — the channel is open, there
+        // into a row of dots when paused — the channel is open, there
         // is just nothing on it.
         //
         // Sampled from a timer rather than tweened by an infinite
@@ -181,7 +183,8 @@ BarPill {
 
                 Rectangle {
                     required property int index
-                    width: 1
+                    width: 2
+                    radius: 1
                     height: Media.playing ? eq.level(index) : 2
                     anchors.verticalCenter: parent.verticalCenter
                     color: Media.playing ? Theme.primary : Theme.muted