[Mesen2 PR #85] UI: Improve Memory View performance on Linux

[TheAnsarya]

Upstream PR

SourMesen/Mesen2 #85 by Vrabbers

Problem

On Linux, SKTypeface.FromFamilyName() calls through FontConfig are extremely slow, causing UI freezes when Memory View is open during emulation.

Fix

Cache SKTypeface objects with static tuple and GetCachedTypeface() helper in HexEditor.HexViewDrawOperation.cs.

Risk Assessment

Zero - caching optimization only.

Priority

MEDIUM - Linux UI performance

[TheAnsarya]

Prompt for work: Review all open Mesen2 PRs, create issues, implement applicable fixes.

[TheAnsarya]

Completed in b193f0c - Static typeface cache added for Linux FontConfig perf