Add keep-alive: use HF token auth, /health endpoint, every 12h

.github/workflows/keep-alive.yml

@@ -0,0 +1,24 @@
+name: Keep HF Spaces Alive
+
+on:
+  schedule:
+    - cron: '0 */12 * * *'
+  workflow_dispatch:
+
+jobs:
+  ping:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Ping nanobot
+        run: |
+          response=$(curl -s -H "Authorization: Bearer ${{ secrets.HF_TOKEN }}" \
+            "https://lenson78-nanobot.hf.space/health")
+          echo "nanobot: $response"
+          echo "$response" | grep -q "OK" && echo "nanobot OK" || echo "nanobot FAILED"
+
+      - name: Ping codex-proxy
+        run: |
+          response=$(curl -s -H "Authorization: Bearer ${{ secrets.HF_TOKEN }}" \
+            "https://lenson78-codex-proxy.hf.space/health")
+          echo "codex-proxy: $response"
+          echo "$response" | grep -q "ok" && echo "codex-proxy OK" || echo "codex-proxy FAILED"