fix(theme): restrict AMOLED overrides to dark theme

[sohan-f]

Prevent AMOLED color replacements from being applied when the app is using a light theme, avoiding unreadable black text on black backgrounds after theme switches.

Problem:

When switching from dark theme to light theme, the AMOLED override continues to apply. This results in black backgrounds and black text, making UI elements (such as keys) unreadable unless the theme is switched back to dark mode.

The AMOLED color override logic was being applied without fully respecting the current UI night mode state, causing previously cached or applied overrides to persist across theme transitions.

Fix:

Restrict AMOLED color overrides to dark mode only by checking the current uiMode before applying any color replacements.

Now overrides are only applied when:

• AMOLED mode is enabled
• The system is in dark theme (UI_MODE_NIGHT_YES)