refactor: one Theme.qml in shared/, symlinked from each component

The four copies had already drifted, which is the argument for doing this
now rather than when a palette change has to be made four times and lands
in three of them. vm-manager was missing surfaceAlt; volume-osd was missing
green, yellow and surfaceAlt. The shared file is the superset, so the two
thin ones gain properties they never had and nothing loses one.

A symlink rather than a shared import path: a singleton outside the config
directory needs a qmldir beside it, the same friction that already keeps
the generated palette parsed rather than imported. Quickshell follows the
link and resolves the singleton with no qmldir, so no consumer changes and
no component stops running standalone under qs -p.

All four load clean with Configuration Loaded and no QML resolution error.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TvHeJEXJzdfAaCCYqURAWp

1 files changed, 66 insertions, 0 deletions

diff --git a/shared/Theme.qml b/shared/Theme.qml
new file mode 100644
index 0000000..423dd49
--- /dev/null
+++ b/shared/Theme.qml
@@ -0,0 +1,66 @@
+// Copyright (C) 2026 Danilo M. <danix@danix.xyz>
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License version 2 as
+// published by the Free Software Foundation.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+pragma Singleton
+
+import Quickshell
+import Quickshell.Io
+import QtQuick
+
+// The palette comes from unified-desktop-theme: udt-accent writes
+// ~/.cache/wal/udt-palette.qml on every wallpaper change, holding the
+// Macchiato colours from its palette.rasi plus the accent snapped from the
+// wallpaper. Watching that file is what makes a theme edit show up here.
+//
+// The defaults below are only what renders before the file is read, or on a
+// machine where unified-desktop-theme is not installed.
+Singleton {
+    id: root
+
+    property color base: "#24273a"
+    property color surface: "#363a4f"
+    property color text: "#cad3f5"
+    property color subtext: "#a5adcb"
+    property color red: "#ed8796"
+    property color green: "#a6da95"
+    property color yellow: "#eed49f"
+    property color surfaceAlt: "#494d64"
+    property color overlay: "#6e738d"
+    property color accent: "#b7bdf8"
+
+    readonly property string fontFamily: "Noto Sans"
+    readonly property int fontSize: 16
+
+    // Parsed rather than imported: a generated file cannot be a QML import
+    // without a qmldir next to it, and the cache directory has no reason to
+    // carry one. The format is fixed and machine-written, so a regex is enough.
+    FileView {
+        path: `${Quickshell.env("HOME")}/.cache/wal/udt-palette.qml`
+        watchChanges: true
+        onFileChanged: reload()
+        onLoaded: {
+            const pick = key => {
+                const m = text().match(new RegExp(`property color ${key}: "(#[0-9a-fA-F]{6})"`));
+                return m ? m[1] : null;
+            };
+            root.base    = pick("base")     ?? root.base;
+            root.surface = pick("surface0") ?? root.surface;
+            root.text    = pick("text")     ?? root.text;
+            root.subtext = pick("subtext0") ?? root.subtext;
+            root.red     = pick("red")      ?? root.red;
+            root.green = pick("green") ?? root.green;
+            root.yellow = pick("yellow") ?? root.yellow;
+            root.surfaceAlt = pick("surface1") ?? root.surfaceAlt;
+            root.overlay = pick("overlay0") ?? root.overlay;
+            root.accent  = pick("accent")   ?? root.accent;
+        }
+    }
+}