refactor: group stow packages into common, mac and kde

Split the packages by platform so each app stays an opt-in Stow package
under common/, mac/ or kde/. KDE gets its own Fastfetch, Helium and
Spectacle packages, and darwin-breeze becomes kde/theme. The READMEs
document stowing a whole group as well as individual packages.

kde/theme/t3/darwin-breeze.json

@@ -0,0 +1,68 @@
+{
+  "version": 1,
+  "name": "Darwin Breeze",
+  "appearance": "dark",
+  "colors": {
+    "canvas": "#181818",
+    "chrome": "#232323",
+    "toolbar": "#232323",
+    "toolbarForeground": "#dfdfdf",
+    "toolbarBorder": "#3a3a3a",
+    "toolbarControl": "#5d5d5d",
+    "toolbarControlForeground": "#e7e7e7",
+    "toolbarControlHover": "#6d6d6d",
+    "surface": "#181818",
+    "surfaceRaised": "#232323",
+    "surfaceOverlay": "#232323",
+    "text": "#dedede",
+    "textMuted": "#9b9b9b",
+    "border": "#313131",
+    "input": "#565656",
+    "focus": "#064b8f",
+    "accent": "#007bff",
+    "accentForeground": "#ffffff",
+    "secondary": "#5d5d5d",
+    "secondaryForeground": "#e7e7e7",
+    "muted": "#232323",
+    "mutedForeground": "#9b9b9b",
+    "placeholder": "#9b9b9b",
+    "secondaryLabel": "#9b9b9b",
+    "iconMuted": "#9b9b9b",
+    "error": "#ff494b",
+    "errorForeground": "#ff494b",
+    "errorSurface": "#311c1e",
+    "warning": "#ff932c",
+    "warningForeground": "#ff932c",
+    "warningSurface": "#31251a",
+    "update": "#3f9dff",
+    "updateForeground": "#3f9dff",
+    "updateSurface": "#1c2936",
+    "accentSurface": "#444444",
+    "accentSurfaceForeground": "#ffffff",
+    "messageSurface": "#232323",
+    "messageForeground": "#dfdfdf",
+    "messageAction": "#007bff",
+    "messageActionForeground": "#ffffff",
+    "messageActionHover": "#1288ff",
+    "codeBackground": "#232323",
+    "codeForeground": "#ffffff",
+    "searchMatchBackground": "#55550e",
+    "searchMatchForeground": "#dedede",
+    "searchMatchActiveBackground": "#ffff00",
+    "searchMatchActiveForeground": "#000000",
+    "sidebar": "#232323",
+    "sidebarForeground": "#dfdfdf",
+    "sidebarMutedForeground": "#9b9b9b",
+    "sidebarControlSurface": "#5d5d5d",
+    "sidebarRowHover": "#3a3a3a",
+    "sidebarRowActive": "#444444",
+    "sidebarRowSelected": "#444444",
+    "sidebarBorder": "#3a3a3a",
+    "terminalBackground": "#181818",
+    "terminalForeground": "#ffffff",
+    "terminalCursor": "#ffffff",
+    "terminalSelection": "#0a4179",
+    "terminalScrollbar": "#565656",
+    "terminalScrollbarHover": "#9b9b9b"
+  }
+}