The contacts list carried its own lowercase-and-compare sort, its own
lowercase substring search, and an inline linear middle-truncation loop
for fitting an address to a column width. These duplicated logic that
belongs in the shared text helpers.
- A new allocation-free case-insensitive compare replaces the per-sort
lowercasing; it lowercases ASCII per byte and leaves bytes >= 0x80
alone, so UTF-8 labels sort exactly as before.
- Search now uses the shared case-insensitive contains helper.
- Middle-truncation to a pixel width moves to a shared template that
binary-searches the fit (about log2(n) width measurements instead of
up to n) while producing the same result as the old linear shrink.
Tests: the compare matches lowercase-then-compare across ASCII, UTF-8
bytes and length ties, and the fit helper matches the old linear loop
across lengths and widths.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>