Refactor and improve active chart settings panel and useChartSettings composable

[jryu01]

Description

Some refactoring related to usChartSettings and active chart settings panel

• Expose activeChartSettings as computed property instead of ref to prevent direct modification from components
• setActiveChartSettings method to set or unset active chart settings
• findAndUpdateChartSettingsById method to find and update chart settings with partial payload instead of having own update method for each chart setting property.
• Make sure activeChartSettings is reactive and updated properly when chartSettings update.
• Added default primary color to the new settings

Resolves #(issue)