feat: add options/map flow, dev seed, and artwork fixes

Options page, Kakao map with florist order message, dev tooling, and
create/message dummy gating — without secrets in .env.example.

Co-authored-by: 이지은 <ijieun@ijieun-ui-MacBookPro.local>
Co-authored-by: Cursor <cursoragent@cursor.com>

static/dev/upload/character.svg

@@ -0,0 +1,6 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="400" height="300" viewBox="0 0 400 300">
+  <rect width="400" height="300" fill="#e8e0f4"/>
+  <circle cx="200" cy="110" r="55" fill="#c4b5d8"/>
+  <rect x="175" y="165" width="50" height="70" rx="20" fill="#9a8ab8"/>
+  <text x="200" y="270" text-anchor="middle" font-size="22" fill="#6b5a82" font-family="Arial">Character</text>
+</svg>