refactor: reorganize flake structure and consolidate user config

Directory structure:
- Move from src/ to root level (system/, user/)
- Remove unused machines (workstation, vm, laptop)

User configuration:
- Add user/home.nix for shared defaults (pass, essentials, default modules)
- Centralize user options in user/default.nix
- Move submodules to consistent paths (bash/bash, git/git, neovim/nvim, vim/vim)

Module reorganization:
- Flatten nested module structures (remove /modules/ subdirs)
- Split CLI vs GUI tools (dev/ for CLI, gui/dev/ for GUI)
- Move neovim/vim to top-level modules (not under utils/)
- Remove security.enable - pass now in user/home.nix
- Remove utils.enable - essentials now in user/home.nix
- Add security/yubikey module with yubikey-manager, age-plugin-yubikey
- Move pcb, design to gui/dev/
- Replace penpot docker wrapper with nixpkgs penpot-desktop
- Remove i3 config
- Remove deprecated wsl.nativeSystemd option

GUI improvements:
- Browser-focused mimeApps in gui/default.nix
- Each WM handles its own auto-start via profileExtra

Cleanup:
- Update README with new structure
- Update justfile paths and valid systems
- Fix submodule paths in .gitmodules

user/modules/gui/wm/hyprland/config/waybar/scripts/weather.sh

@@ -0,0 +1,24 @@
+#!/bin/sh
+BSSIDS="$(nmcli device wifi list |
+    awk 'NR>1 {if ($1 != "*") {print $1}}' |
+    tr -d ":" |
+    tr "\n" ",")"
+
+LOC=""
+REQUEST_GEO="$(wget -qO - http://openwifi.su/api/v1/bssids/"$BSSIDS")"
+if [[ "$(jq ".count_results" <<< "$REQUEST_GEO")" -gt 0 ]] ; then
+    LAT="$(jq ".lat" <<< "$REQUEST_GEO")"
+    LON="$(jq ".lon" <<< "$REQUEST_GEO")"
+    LOC="$LAT,$LON"
+fi
+
+text="$(curl -s "https://wttr.in/$LOC?format=1" | sed 's/ //g')"
+tooltip="$(curl -s "https://wttr.in/$LOC?0QT" |
+    sed 's/\\/\\\\/g' |
+    sed ':a;N;$!ba;s/\n/\\n/g' |
+    sed 's/"/\\"/g')"
+
+if ! grep -q "Unknown location" <<< "$text"; then
+    echo "{\"text\": \"$text\", \"tooltip\": \"<tt>$tooltip</tt>\", \"class\": \"weather\"}"
+fi
+