feat(preset): add MiniMax as official partner with Black Friday promotion

- Mark MiniMax as partner with custom theme color (#f64551)
- Add Black Friday promotional text for Starter plan ($2/mo, 80% OFF)
- Update apiKeyUrl to MiniMax coding plan subscription page

src/config/claudeProviderPresets.ts

@@ -220,7 +220,7 @@ export const providerPresets: ProviderPreset[] = [
   {
     name: "MiniMax",
     websiteUrl: "https://platform.minimaxi.com",
-    apiKeyUrl: "https://platform.minimaxi.com/user-center/basic-information",
+    apiKeyUrl: "https://platform.minimax.io/subscribe/coding-plan",
     settingsConfig: {
       env: {
         ANTHROPIC_BASE_URL: "https://api.minimaxi.com/anthropic",
@@ -234,6 +234,12 @@ export const providerPresets: ProviderPreset[] = [
       },
     },
     category: "cn_official",
+    isPartner: true,
+    partnerPromotionKey: "minimax",
+    theme: {
+      backgroundColor: "#f64551",
+      textColor: "#FFFFFF",
+    },
   },
   {
     name: "DouBaoSeed",