perf: optimize tag classes and text width calculations for faster zoom/pan

[Kayd-06]

Fixes #11832

This PR improves zoom and pan performance by reducing unnecessary work during SVG redraws:

• Cache tag class computation based on entity version to avoid repeated recalculation
• Reuse a persistent DOM node for text width measurement instead of recreating it
• Avoid redundant tagClasses() calls by limiting them to enter selections
• Stabilize tag handling for ways (e.g. multipolygons) so caching works correctly

These changes significantly reduce time spent in drawEditable and improve responsiveness during map interaction.