feat(kilo): fetch free models from Kilo API + Windows build fixes (#455)

- Add /api/providers/kilo/free-models endpoint with 1hr cache
- Fetch and merge Kilo free models with hardcoded models for kilocode provider
- Display 'Free' badge on models fetched from Kilo API
- Fix Windows build: add cross-env, remove --webpack flag, add turbopack config
- Add outputFileTracingExcludes for Windows system directories

src/app/api/providers/kilo/free-models/route.js

@@ -0,0 +1,55 @@
+import { NextResponse } from "next/server";
+
+const KILO_MODELS_URL = "https://api.kilo.ai/api/gateway/models";
+
+// In-memory cache with TTL
+let cachedModels = null;
+let cacheTimestamp = 0;
+const CACHE_TTL_MS = 60 * 60 * 1000; // 1 hour
+
+export async function GET() {
+  const now = Date.now();
+
+  // Return cached result if still valid
+  if (cachedModels && now - cacheTimestamp < CACHE_TTL_MS) {
+    return NextResponse.json({ models: cachedModels, cached: true });
+  }
+
+  try {
+    const res = await fetch(KILO_MODELS_URL, {
+      headers: { "Accept": "application/json" },
+      signal: AbortSignal.timeout(10000),
+    });
+
+    if (!res.ok) {
+      throw new Error(`Kilo API returned ${res.status}`);
+    }
+
+    const json = await res.json();
+    const allModels = json.data || [];
+
+    const freeModels = allModels
+      .filter((m) => m.isFree === true)
+      .map((m) => ({
+        id: m.id,
+        name: m.name,
+        isFree: true,
+        context_length: m.context_length || 0,
+      }));
+
+    cachedModels = freeModels;
+    cacheTimestamp = now;
+
+    return NextResponse.json({ models: freeModels, cached: false });
+  } catch (error) {
+    // Return cached data if available, even if expired
+    if (cachedModels) {
+      return NextResponse.json({ models: cachedModels, cached: true, warning: error.message });
+    }
+
+    return NextResponse.json(
+      { models: [], error: `Failed to fetch Kilo models: ${error.message}` },
+      { status: 502 }
+    );
+  }
+}