ClearChat Home v1.4.2 - Widget Settings Save/Preview Fix

Patch-only update.

Fixes:
- Removes duplicate checkmark in color palette.
- Improves live preview contrast/readability.
- Forces settings API responses to no-cache.
- Validates widget_color in settings API.
- Public widget reloads latest settings when chat button is opened.
- Public widget applies saved color/status more reliably after settings changes.
- Bumps version to 1.4.2-home.

After applying:
1. Hard-refresh the admin Settings page.
2. Pick a color and Save Settings.
3. Hard-refresh the public website page once.
4. Reopen the chat widget. It should fetch the newest color/status.
