feat: implement modular foundation and core system services

- Update flake.nix with 25.11 release and core inputs
- Add dedicated modules for audio (Pipewire), bluetooth, and networking
- Update GEMINI.md with the new Modular Merging Architecture blueprint
- Configure graphical installer ISO and test VM outputs

bin/nomarchy-theme-bg-next

@@ -1,50 +1,56 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
-# Cycles through the background images available
+# Cycles through the background images available for the current theme.
+# Declarative + Hybrid (instant swww) for Nomarchy NixOS.
 
-THEME_NAME=$(cat "$HOME/.config/nomarchy/current/theme.name" 2>/dev/null)
-THEME_BACKGROUNDS_PATH="$HOME/.config/nomarchy/current/theme/backgrounds/"
-USER_BACKGROUNDS_PATH="$HOME/.config/nomarchy/backgrounds/$THEME_NAME/"
-CURRENT_BACKGROUND_LINK="$HOME/.config/nomarchy/current/background"
+STATE_DIR="$HOME/.config/home-manager"
+THEME_STATE_FILE="$STATE_DIR/theme-state.nix"
+WALLPAPER_STATE_FILE="$STATE_DIR/wallpaper-state.nix"
 
-mapfile -d '' -t BACKGROUNDS < <(find -L "$USER_BACKGROUNDS_PATH" "$THEME_BACKGROUNDS_PATH" -maxdepth 1 -type f -print0 2>/dev/null | sort -z)
+THEME_NAME=$(cat "$THEME_STATE_FILE" 2>/dev/null || echo "dracula")
+
+if [ -d "/etc/nixos/nomarchy/themes" ]; then
+  THEMES_DIR="/etc/nixos/nomarchy/themes"
+elif [ -d "/etc/nomarchy/themes" ]; then
+  THEMES_DIR="/etc/nomarchy/themes"
+else
+  THEMES_DIR="/etc/nixos/themes"
+fi
+
+BG_DIR="$THEMES_DIR/$THEME_NAME/backgrounds"
+
+if [ ! -d "$BG_DIR" ]; then
+    notify-send "No background directory found for theme $THEME_NAME"
+    exit 1
+fi
+
+mapfile -t BACKGROUNDS < <(ls "$BG_DIR" | sort)
 TOTAL=${#BACKGROUNDS[@]}
 
 if (( TOTAL == 0 )); then
-  notify-send "No background was found for theme" -t 2000
-  pkill -x swaybg
-  setsid uwsm-app -- swaybg --color '#000000' >/dev/null 2>&1 &
-else
-  # Get current background from symlink
-  if [[ -L $CURRENT_BACKGROUND_LINK ]]; then
-    CURRENT_BACKGROUND=$(readlink "$CURRENT_BACKGROUND_LINK")
-  else
-    # Default to first background if no symlink exists
-    CURRENT_BACKGROUND=""
-  fi
-
-  # Find current background index
-  INDEX=-1
-  for i in "${!BACKGROUNDS[@]}"; do
-    if [[ ${BACKGROUNDS[$i]} == $CURRENT_BACKGROUND ]]; then
-      INDEX=$i
-      break
-    fi
-  done
-
-  # Get next background (wrap around)
-  if (( INDEX == -1 )); then
-    # Use the first background when no match was found
-    NEW_BACKGROUND="${BACKGROUNDS[0]}"
-  else
-    NEXT_INDEX=$(((INDEX + 1) % TOTAL))
-    NEW_BACKGROUND="${BACKGROUNDS[$NEXT_INDEX]}"
-  fi
-
-  # Set new background symlink
-  ln -nsf "$NEW_BACKGROUND" "$CURRENT_BACKGROUND_LINK"
-
-  # Relaunch swaybg
-  pkill -x swaybg
-  setsid uwsm-app -- swaybg -i "$CURRENT_BACKGROUND_LINK" -m fill >/dev/null 2>&1 &
+    notify-send "No backgrounds found in $BG_DIR"
+    exit 1
 fi
+
+CURRENT_BG=$(cat "$WALLPAPER_STATE_FILE" 2>/dev/null)
+INDEX=-1
+for i in "${!BACKGROUNDS[@]}"; do
+    if [[ "$BG_DIR/${BACKGROUNDS[$i]}" == "$CURRENT_BG" ]]; then
+        INDEX=$i
+        break
+    fi
+done
+
+NEXT_INDEX=$(((INDEX + 1) % TOTAL))
+NEW_BG="$BG_DIR/${BACKGROUNDS[$NEXT_INDEX]}"
+
+echo "$NEW_BG" > "$WALLPAPER_STATE_FILE"
+
+# Instant feedback via swww
+if pgrep -x swww-daemon >/dev/null; then
+    swww img "$NEW_BG" --transition-type outer --transition-pos 0.85,0.97 --transition-step 90
+else
+    swww init && swww img "$NEW_BG"
+fi
+
+echo "Background set to $NEW_BG declaratively."