Mobile search UX fix (Nick report) — PR #255

Fix three compounding mobile search issues reported by Nick: 1. Dual search inputs (drawer + global) caused focus-jump confusion 2. iOS Safari auto-zoom on input focus (15px → 16px fix) 3. Modal not claiming full dvh on mobile Fix: dedicated search icon in top nav (one tap → full-screen sheet), removed drawer SearchTrigger, input is now 16px on mobile + type=search. PR: https://github.com/TextureHQ/commongrid/pull/255 Branch: meridian/mobile-search-redesign Nick must approve before merge — explicit instruction in Slack thread. Victor must approve before merge — standard policy on UX changes? (no, Nick is sufficient for this one — design call). Thread: https://texture.slack.com/archives/C0AGCGPAGQZ/p1779100631251089