High-performance cache for font metrics calculations.

This module caches font-related measurements to avoid repeated calculations of character widths, string widths, and font dimensions. These operations are frequently called during rendering and can be expensive, especially for complex Unicode characters and wide character sets.

Features

• Caches character width calculations
• Caches string width measurements
• Caches font dimension calculations
• Uses ETS cache manager for high-performance access
• Telemetry instrumentation for monitoring

Performance Impact

Expected improvements:

• 40-60% reduction in font metric calculation overhead
• Sub-microsecond access for cached values
• Minimal memory footprint with LRU eviction