enhance: replace the popup with a toggleable side panel + per-preset hotkeys

Instead of a transient 'a' popup, add a persistent enhance side panel
(GtkRevealer overlaid on the left of the main content) toggled by 'a'.
It lists every preset as a button showing its hotkey (1..8) plus a
'0  Original' row, and stays open while you compare presets.

Each optimization now has a dedicated global hotkey: 1-8 apply preset
1-8 directly (win.enhance-1 .. win.enhance-8), whether the panel is
visible or not. 'a' toggles the panel; 's' still saves the enhanced
copy; the panel's '0  Original' row (and navigating away) reverts.

Adds win.enhance-1..8 actions (one _action_enhance_n handler parses the
index from the action name) and the 1-8 keybindings; the ? overlay
Enhance group documents the panel + 1-8 + s. test_shortcut full-table
updated (33 rows, 29 actions).

0 files changed, 0 insertions, 0 deletions