refactor: implement component-based architecture for enhanced maintainability

- Reorganize directory structure into core/, features/, and themes/
- Colocate application Nix logic, configs, scripts, and theme overrides
- Implement 'Inversion of Control' for theming: apps now pull theme-specific layouts
- Update flake.nix and shared library paths to match the new structure
- Document the new Feature-Centric architecture in README.md

features/scripts/utils/nomarchy-cmd-share

@@ -0,0 +1,46 @@
+#!/bin/bash
+
+# Share clipboard, file, or folder using LocalSend. Bound to Super + Ctrl + S by default.
+
+if (($# == 0)); then
+  echo "Usage: nomarchy-cmd-share [clipboard|file|folder]"
+  exit 1
+fi
+
+MODE="$1"
+shift
+
+if [[ $MODE == "clipboard" ]]; then
+  TEMP_FILE=$(mktemp --suffix=.txt)
+  wl-paste >"$TEMP_FILE"
+  FILES="$TEMP_FILE"
+else
+  if (($# > 0)); then
+    FILES="$*"
+  else
+    if [[ $MODE == "folder" ]]; then
+      # Pick a single folder from home directory
+      FILES=$(find "$HOME" -type d 2>/dev/null | fzf)
+    else
+      # Pick one or more files from home directory
+      FILES=$(find "$HOME" -type f 2>/dev/null | fzf --multi)
+    fi
+    [[ -z $FILES ]] && exit 0
+  fi
+fi
+
+# Run LocalSend in its own systemd service (detached from terminal)
+# Convert newline-separated files to space-separated arguments
+if [[ $MODE != "clipboard" ]] && echo "$FILES" | grep -q $'\n'; then
+  # Multiple files selected - convert newlines to array
+  readarray -t FILE_ARRAY <<<"$FILES"
+  systemd-run --user --quiet --collect localsend --headless send "${FILE_ARRAY[@]}"
+else
+  # Single file or clipboard mode
+  systemd-run --user --quiet --collect localsend --headless send "$FILES"
+fi
+
+# Note: Temporary file will remain until system cleanup for clipboard mode
+# This ensures the file content is available for the LocalSend GUI
+
+exit 0