Final retrofit in the cross-project iOS focus-zoom chore (after authd PR
#11, buchinese PR #5, inventory PR #18, movement PR #15). Enforces the
standing rule in ~/.claude/CLAUDE.md: text-entry inputs must compute to
font-size >= 16px so iOS Safari does not auto-zoom on focus.
Removes the IBM Plex Mono Google Fonts @import, replaces the --font CSS
variable with a cross-platform system sans-serif stack, and adds a
--font-mono variable for the share-URL readonly input so copy/share text
stays monospace. Also adds line-height: 1.5 to body to compensate for
the system fonts' tighter default leading.
No font asset files exist in /public; layout.ts has no font <link> tags
to remove. Acceptance check: build + 112 tests pass; new
tests/integration/style.test.ts asserts no @import / IBM Plex / external
font URL remains and that the system stack is wired up.
