fix: swap foreground/background colors in completion menu current item

[karesansui-u]

Bug description

The completion-menu.completion.current style in io.py has its foreground and background colors reversed compared to the non-current completion-menu style.

The non-current (correct) pattern:

# completion-menu — correct
f"bg:{self.completion_menu_bg_color}"     # bg: prefix → background
self.completion_menu_color                 # no prefix → foreground

The current-item (swapped) pattern:

# completion-menu.completion.current — swapped
self.completion_menu_current_bg_color      # no bg: prefix → applied as foreground
f"bg:{self.completion_menu_current_color}" # bg: prefix → applied as background

Steps to reproduce

aider --completion-menu-current-color '#FFFFFF' --completion-menu-current-bg-color '#0000FF'

1. Type to trigger the completion menu (Tab)
2. Expected: Blue background with white text on the selected item
3. Actual: White background with blue text (inverted)

Fix

Apply the bg: prefix to completion_menu_current_bg_color and remove it from completion_menu_current_color, matching the pattern used for the non-current menu style.

Affected files

• aider/io.py (L424-427) — 2 line change