feat(presets): add Amux provider preset for 6 apps

Non-partner aggregator across Claude Code, Claude Desktop, Codex,
OpenCode, OpenClaw, and Hermes. Claude Code uses bare host
api.amux.ai; Codex uses /v1 native Responses; the other three apps
default to gpt-5.5. No Gemini preset. Registers the amux inline icon
(currentColor) in the icon index and metadata.

src/config/codexProviderPresets.ts

@@ -350,6 +350,20 @@ export const codexProviderPresets: CodexProviderPreset[] = [
     partnerPromotionKey: "teamorouter",
     icon: "teamorouter",
   },
+  {
+    name: "Amux",
+    websiteUrl: "https://amux.ai",
+    apiKeyUrl: "https://amux.ai",
+    category: "aggregator",
+    auth: generateThirdPartyAuth(""),
+    config: generateThirdPartyConfig(
+      "amux",
+      "https://api.amux.ai/v1",
+      "gpt-5.5",
+    ),
+    endpointCandidates: ["https://api.amux.ai/v1"],
+    icon: "amux",
+  },
   {
     name: "Azure OpenAI",
     websiteUrl: