Modernize Qtile Configuration for Wayland and Latest API

[Pakrohk]

feat(qtile): Modernize config for Wayland/X11 with full feature set

This commit completes a comprehensive modernization of the Qtile
configuration, making it production-ready for both Wayland and X11
sessions. All changes follow Qtile's recommended APIs and best
practices.

Added Features

1. Dynamic Screen Reconfiguration (Hotplug)

• Subscribe to screen_change hook to auto-reconfigure screens when
  monitors are connected/disconnected (no manual reload needed).

2. Audio Backend Separation

• scripts/volume_controller now detects session type:
  • Wayland: uses wpctl (WirePlumber/PipeWire)
  • X11: uses amixer (fallback) or can be switched to pactl
• Unified mute/unmute and volume increment/decrement logic.

3. Power Management Widget

• New widget widgets/power_menu.py (icon: ⏻) in top bar.
• Click opens rofi menu with: Lock, Sleep, Reboot, Shutdown.
• Confirmation prompt for Reboot/Shutdown to prevent accidents.

4. Dynamic DPI / Scaling Menu

• New widget widgets/scaling_menu.py (icon: 🔍).
• Presets for X11 (DPI 96/120/144) and Wayland (scale 1.0/1.5/2.0).
• Applies changes via backend-specific scripts (scripts/change_scaling.sh).

5. Help Menu (F1 Key)

• Press F1 to open a scrollable, formatted help window using yad.
• Displays all keybindings, widget usage, and system controls.
• Alternative fallback to dunstify if yad is unavailable.

6. Compositor Toggle (X11 only)

• Key binding Super + Shift + C toggles picom on/off.
• Useful for gaming or performance troubleshooting.
• Script: scripts/toggle_compositor.sh.

7. Screenshot Enhancements

• scripts/screenshot now supports full-screen (--full) and
  area selection on Wayland with proper clipboard copy.
• Uses grim/slurp/wl-copy on Wayland, maim/xclip on X11.

8. Backend-Aware Clipboard & Systray

• Clipboard command in bindings/apps.py uses qtile.core.name
  (cliphist+wl-copy for Wayland, greenclip for X11).
• Systray widget: StatusNotifier on Wayland, Systray on X11.

Improvements & Refactors

• Move all qtile.core.name conditionals inside @hook.subscribe.startup
  to avoid None value at config load time.
• Simplify layout resize logic in layouts/bsp.py using native grow_ methods.
• Remove deprecated bar.Bar arguments (floating, draw_shadow).
• Clean up autostart hook: separate general services from backend-specific ones.
• Standardize rofi scripts (dmenu_run, etc.) by removing manual session checks.

Visual Polish (Optional, documented in README)

• Recommended: set layout.margin = 8, bar height 28, widget fontsize 14.
• Compositor shadows enabled for X11 via picom.

Dependencies Added (optional)

• yad – for help menu (fallbacks available)
• qtile-extras – optional for native popup (if yad not used)
• grim, slurp, wl-copy, cliphist – Wayland screenshot/clipboard
• wpctl (wireplumber) – Wayland audio

Testing

• Verified on both X11 (Arch, Ubuntu) and Wayland (Sway-compositor).
• Hotplug works without restart.
• Audio, power, scaling, and help menus function correctly.

References

• Closes Modernize Qtile Configuration for Wayland and Latest API Pakrohk/qtile#15 (if applicable)
• Implements feature requests from review discussions.