feat: unify Qt5, Qt6 and GTK on Macchiato with a lavender accent

Installs the upstream Catppuccin Kvantum and GTK themes and points all four
toolkits at them. Qt5 and Qt6 previously disagreed with each other as well as
with the desktop: qt5ct carried a hand-rolled grey/purple palette and qt6ct used
the stock darker.conf. Both now take their palette from Kvantum.

Two things were not where they looked. GTK3's theme comes from gsettings on
Wayland, not settings.ini, and gsettings was pinned to Breeze, which silently
overrode the file; its icon-theme was likewise on breeze-dark while
settings.ini said Material-Black-Plum-Suru. GTK4 ignores gtk-theme-name
entirely, so its stylesheet is symlinked into ~/.config/gtk-4.0 instead.

The accent is fixed rather than wallpaper-tracking, since Qt and GTK apps only
reread a theme on restart. Lavender also replaces mauve as udt-accent's
fallback so everything without a wallpaper-derived accent agrees.

catppuccin/gtk is archived upstream. v1.0.3 works today but will not track
future libadwaita changes; it is removable by deleting the directory.

The tracked qt5ct/qt6ct files carry only the theme-relevant keys: the live
files also hold an ignored_applications list of local paths.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01G6aeE37K4GHBsaM51yLTTq

6 files changed, 98 insertions, 0 deletions

diff --git a/templates/qt-gtk/README.md b/templates/qt-gtk/README.md
new file mode 100644
index 0000000..c7c951b
--- /dev/null
+++ b/templates/qt-gtk/README.md
@@ -0,0 +1,40 @@
+# Qt and GTK
+
+Catppuccin Macchiato with a **lavender** accent, fixed rather than
+wallpaper-tracking: Qt and GTK apps only pick up a theme change when they
+restart, so a moving accent would leave running apps disagreeing with new ones.
+
+Lavender is also `udt-accent`'s fallback, so anything without a wallpaper-derived
+accent lands on the same colour.
+
+## Upstream themes
+
+Neither is generated by this repo; both are installed from upstream.
+
+| | Theme | Source |
+| --- | --- | --- |
+| Qt5 + Qt6 | `catppuccin-macchiato-lavender` | `catppuccin/Kvantum` |
+| GTK3 + GTK4 | `catppuccin-macchiato-lavender-standard+default` | `catppuccin/gtk` v1.0.3 |
+
+`catppuccin/gtk` is **archived upstream**. v1.0.3 works and is what the
+ecosystem uses, but it will not track future GTK4/libadwaita changes. Removing
+it is just deleting the directory from `~/.themes`.
+
+## Wiring
+
+- **Qt5/Qt6**: `style=kvantum-dark` in both `qt5ct.conf` and `qt6ct.conf`, with
+  `custom_palette=false` so Kvantum supplies the palette. Previously the two
+  disagreed: qt5ct used a hand-rolled grey/purple scheme and qt6ct used
+  `/usr/share/qt6ct/colors/darker.conf`.
+- **GTK3**: the theme name has to be set with **gsettings**, not just
+  `settings.ini`. On Wayland gsettings wins, and it was pinned to `Breeze`,
+  which silently overrode the file. `icon-theme` was likewise stuck on
+  `breeze-dark` while `settings.ini` said `Material-Black-Plum-Suru`.
+- **GTK4**: libadwaita ignores `gtk-theme-name`, so `~/.config/gtk-4.0/theme`
+  is a symlink to the theme's `gtk-4.0` directory and `gtk.css` imports it.
+
+## Reproducing
+
+    gsettings set org.gnome.desktop.interface gtk-theme 'catppuccin-macchiato-lavender-standard+default'
+    gsettings set org.gnome.desktop.interface icon-theme 'Material-Black-Plum-Suru'
+    gsettings set org.gnome.desktop.interface color-scheme 'prefer-dark'
diff --git a/templates/qt-gtk/gtk3-settings.ini b/templates/qt-gtk/gtk3-settings.ini
new file mode 100644
index 0000000..a35a2ea
--- /dev/null
+++ b/templates/qt-gtk/gtk3-settings.ini
@@ -0,0 +1,21 @@
+[Settings]
+gtk-application-prefer-dark-theme=true
+gtk-button-images=1
+gtk-cursor-theme-name=Oxygen_Zion
+gtk-cursor-theme-size=24
+gtk-decoration-layout=icon:minimize,maximize,close
+gtk-enable-animations=true
+gtk-font-name=Noto Sans,  10
+gtk-icon-theme-name=Material-Black-Plum-Suru
+gtk-menu-images=1
+gtk-modules=colorreload-gtk-module:window-decorations-gtk-module
+gtk-primary-button-warps-slider=false
+gtk-theme-name=catppuccin-macchiato-lavender-standard+default
+gtk-toolbar-style=GTK_TOOLBAR_BOTH_HORIZ
+gtk-xft-dpi=98304
+gtk-toolbar-icon-size=GTK_ICON_SIZE_LARGE_TOOLBAR
+gtk-enable-event-sounds=1
+gtk-enable-input-feedback-sounds=1
+gtk-xft-antialias=1
+gtk-xft-hinting=1
+gtk-xft-hintstyle=hintmedium
diff --git a/templates/qt-gtk/gtk4-gtk.css b/templates/qt-gtk/gtk4-gtk.css
new file mode 100644
index 0000000..9bf52c0
--- /dev/null
+++ b/templates/qt-gtk/gtk4-gtk.css
@@ -0,0 +1,10 @@
+/* Catppuccin Macchiato (lavender) for GTK4 / libadwaita.
+ * libadwaita ignores gtk-theme-name, so the theme's own stylesheet is imported
+ * here instead. Assets are symlinked next to this file. */
+@import url("theme/gtk.css");
+
+/* vte terminal: local override, kept from the previous config. */
+VteTerminal {
+    padding: 10px;
+    -VteTerminal-inner-border: 10px;
+}
diff --git a/templates/qt-gtk/kvantum.kvconfig b/templates/qt-gtk/kvantum.kvconfig
new file mode 100644
index 0000000..aa0ae60
--- /dev/null
+++ b/templates/qt-gtk/kvantum.kvconfig
@@ -0,0 +1,2 @@
+[General]
+theme=catppuccin-macchiato-lavender
diff --git a/templates/qt-gtk/qt5ct.conf b/templates/qt-gtk/qt5ct.conf
new file mode 100644
index 0000000..925d422
--- /dev/null
+++ b/templates/qt-gtk/qt5ct.conf
@@ -0,0 +1,12 @@
+# Theme-relevant keys only; the live file carries other settings.
+[Appearance]
+custom_palette=false
+icon_theme=Material-Black-Plum-Suru
+standard_dialogs=xdgdesktopportal
+style=kvantum-dark
+[Fonts]
+fixed="Inconsolata Nerd Font Mono,14,-1,5,50,0,0,0,0,0"
+general="Noto Sans,14,-1,5,50,0,0,0,0,0,Regular"
+[Interface]
+[SettingsWindow]
+[Troubleshooting]
diff --git a/templates/qt-gtk/qt6ct.conf b/templates/qt-gtk/qt6ct.conf
new file mode 100644
index 0000000..b8b0054
--- /dev/null
+++ b/templates/qt-gtk/qt6ct.conf
@@ -0,0 +1,13 @@
+# Theme-relevant keys only; the live file carries other settings.
+[Appearance]
+custom_palette=false
+icon_theme=Material-Black-Plum-Suru
+standard_dialogs=xdgdesktopportal
+style=kvantum-dark
+[Fonts]
+fixed="Inconsolata Nerd Font Mono,14,-1,5,400,0,0,0,0,0,0,0,0,0,0,1,,0,0"
+general="Noto Sans,14,-1,5,400,0,0,0,0,0,0,0,0,0,0,1,Regular,0,0"
+[Interface]
+[QSSEditor]
+[SettingsWindow]
+[Troubleshooting]