v0.3.0

Changelog

• f869259 feat: introduce Renderer interface and open View to custom render strategies
• af0b36f fix: visual label width via lipgloss.Width, renderGrid consolidation, strict endpoint test, and customTicks sorting
• 976604d refactor: add formatValue helper, implement fmt.Stringer, remove unused canvas package
• f9f9cde refactor: resolve SRP and DRY violations in View, grid, styles, and normalization
• df82b6f refactor: simplify series state to single source of truth and unify Option delegation to Setters