feat: swap AI model to x-ai/grok-4.3 and add PoweredByBanner component

artifacts/api-server/src/lib/feasibility.ts

@@ -63,7 +63,7 @@ Build: ${build?.name ?? "unknown"}
 Generate the feasibility report. Strict JSON only.`;
 
   const response = await openrouter.chat.completions.create({
-    model: "deepseek/deepseek-v4-flash",
+    model: "x-ai/grok-4.3",
     max_tokens: 1500,
     messages: [
       { role: "system", content: SYSTEM_PROMPT },

artifacts/api-server/src/lib/personaReply.ts

@@ -31,7 +31,7 @@ Voice rules (apply to ALL bots, then layer your personal flavor on top):
 Now stay in character.`;
 
   const response = await openrouter.chat.completions.create({
-    model: "deepseek/deepseek-v4-flash",
+    model: "x-ai/grok-4.3",
     max_tokens: 400,
     messages: [
       { role: "system", content: system },

artifacts/marsfounder/src/components/PoweredByBanner.tsx

@@ -0,0 +1,76 @@
+const WORDMARK_FONT = "'Inter', 'Arial', sans-serif";
+
+export function PoweredByBanner() {
+  return (
+    <div className="flex flex-wrap items-center justify-center gap-4 sm:gap-6 opacity-50 hover:opacity-70 transition-opacity duration-300">
+      <span className="font-mono text-[10px] tracking-widest uppercase text-muted-foreground/70 whitespace-nowrap">
+        Powered by
+      </span>
+
+      {/* xAI wordmark */}
+      <svg
+        viewBox="0 0 64 24"
+        height="14"
+        aria-label="xAI"
+        fill="currentColor"
+        className="text-foreground/80"
+      >
+        <text
+          x="0"
+          y="19"
+          fontFamily={WORDMARK_FONT}
+          fontWeight="800"
+          fontSize="20"
+          letterSpacing="-0.5"
+        >
+          xAI
+        </text>
+      </svg>
+
+      <span className="w-px h-3 bg-border/50" aria-hidden="true" />
+
+      {/* Grok wordmark */}
+      <svg
+        viewBox="0 0 72 24"
+        height="14"
+        aria-label="Grok"
+        fill="currentColor"
+        className="text-foreground/80"
+      >
+        <text
+          x="0"
+          y="19"
+          fontFamily={WORDMARK_FONT}
+          fontWeight="700"
+          fontSize="20"
+          letterSpacing="-0.5"
+        >
+          Grok
+        </text>
+      </svg>
+
+      <span className="w-px h-3 bg-border/50" aria-hidden="true" />
+
+      {/* SpaceX wordmark */}
+      <svg
+        viewBox="0 0 104 24"
+        height="14"
+        aria-label="SpaceX"
+        fill="currentColor"
+        className="text-foreground/80"
+      >
+        <text
+          x="0"
+          y="19"
+          fontFamily={WORDMARK_FONT}
+          fontWeight="800"
+          fontSize="20"
+          fontStyle="italic"
+          letterSpacing="-0.5"
+        >
+          SpaceX
+        </text>
+      </svg>
+    </div>
+  );
+}

artifacts/marsfounder/src/components/layout.tsx

@@ -1,4 +1,5 @@
 import { Link, useLocation } from "wouter";
+import { PoweredByBanner } from "@/components/PoweredByBanner";
 import { 
   useGetMarsTime, 
   useGetLightDelay, 
@@ -102,8 +103,9 @@ export function Layout({ children }: { children: React.ReactNode }) {
           </div>
         </div>
 
-        <div className="max-w-7xl mx-auto mt-12 pt-4 border-t border-border/50 flex justify-between items-center text-[10px] font-mono text-muted-foreground/50">
+        <div className="max-w-7xl mx-auto mt-12 pt-4 border-t border-border/50 flex flex-col sm:flex-row justify-between items-center gap-4 text-[10px] font-mono text-muted-foreground/50">
           <span>© 2026 MARSFOUNDER INC.</span>
+          <PoweredByBanner />
           <span>NOT AFFILIATED WITH NASA OR SPACEX.</span>
         </div>
       </footer>

documentation/architecture.md

@@ -53,7 +53,7 @@ Browser → Vercel (SPA) → VPS Docker container (Express API) → Neon Postgre
 - **Framework**: Express 5, TypeScript
 - **Build**: esbuild → single CJS bundle at `dist/index.mjs`
 - **Database access**: Drizzle ORM via `@workspace/db`
-- **AI**: `@workspace/integrations-anthropic-ai` (OpenRouter via `openai` SDK, model `deepseek/deepseek-v4-flash`)
+- **AI**: `@workspace/integrations-anthropic-ai` (OpenRouter via `openai` SDK, model `x-ai/grok-4.3`)
 - **Rate limiting**: 
   - AI routes (`/api/personas/*`, `/api/missions/:id/feasibility`): 15 req/min
   - Write routes (`POST /api/builds`, `POST /api/missions`): 30 req/min
@@ -82,7 +82,7 @@ File: `lib/integrations-anthropic-ai/src/client.ts`
 
 Uses the `openai` SDK pointed at OpenRouter:
 - `baseURL`: `https://openrouter.ai/api/v1`
-- Model: `deepseek/deepseek-v4-flash`
+- Model: `x-ai/grok-4.3`
 - Headers: `HTTP-Referer`, `X-Title`
 - Env var: `OPENROUTER_API_KEY`