Use per-exchange PWA names and logos for instance app installs.

Show Binance/OKX/Gate 交易系统 with distinct exchange icons in manifests, apple titles, and login branding.

Co-authored-by: Cursor <cursoragent@cursor.com>

brand/icons/binance/icon.svg

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+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512">
+  <rect width="512" height="512" rx="108" fill="#0c1019"/>
+  <rect x="36" y="36" width="440" height="440" rx="88" fill="#141b2d"/>
+  <rect x="36" y="36" width="440" height="440" rx="88" fill="none" stroke="#F0B90B" stroke-width="12"/>
+  <polygon points="256,150 362,256 256,362 150,256" fill="#F0B90B"/><polygon points="256,210 302,256 256,302 210,256" fill="#1a160a"/>
+</svg>

brand/icons/gate/icon.svg

@@ -0,0 +1,6 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512">
+  <rect width="512" height="512" rx="108" fill="#0c1019"/>
+  <rect x="36" y="36" width="440" height="440" rx="88" fill="#141b2d"/>
+  <rect x="36" y="36" width="440" height="440" rx="88" fill="none" stroke="#17E6A1" stroke-width="12"/>
+  <text x="256" y="310" text-anchor="middle" font-family="Arial, Helvetica, sans-serif" font-size="220" font-weight="700" fill="#17E6A1">G</text>
+</svg>

brand/icons/okx/icon.svg

@@ -0,0 +1,6 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512">
+  <rect width="512" height="512" rx="108" fill="#0c1019"/>
+  <rect x="36" y="36" width="440" height="440" rx="88" fill="#141b2d"/>
+  <rect x="36" y="36" width="440" height="440" rx="88" fill="none" stroke="#FFFFFF" stroke-width="12"/>
+  <rect x="168" y="168" width="72" height="72" rx="10" fill="#FFFFFF"/><rect x="272" y="168" width="72" height="72" rx="10" fill="#FFFFFF"/><rect x="168" y="272" width="72" height="72" rx="10" fill="#FFFFFF"/>
+</svg>