feat: improvements to make more composable

[francisashley]

• feat: Removed spreadsheet view. Direct cell modifications are currently out of scope. For row editing support, consider creating a custom modal with a form for remote editing.
• feat: Added VueScreener suffix to all components to clearly indicate package origin.
• ref: Renamed terminology from "item" to "row". VueScreener now consistently uses "rows", "columns" and "cells".
• feat: Made vue-screener state prop optional. Component defaults to internal state, with option for remote control override.
• ui: Replaced icons with codicon to simplify codebase and improve ui.
• feat: Implemented tailwind-merge for class handling. Override tailwind classes without needing ! prefix.
• feat: Enhanced composability support. Rather than configuring via a large UI prop, VueScreener now offers two approaches: a base component with minimal control, or individual customizable components. This promotes more declarative styling by reducing the gap between components and their styles.
• ref: Simplified prop naming conventions.