init: info-canicule MVP (Vigilance + climato + conseils)

Astro 5 SSR + ioredis cache Valkey, déployable sur shared-net.
- Vigilance temps réel via Opendatasoft (no-auth, LOv2)
- Carte SVG des 96 départements (gregoiredavid/france-geojson)
- Climato T° 30j par dept (CSV.GZ Météo France, cache 24h)
- Conseils officiels par phénomène (7 types Vigilance)
- /api/health (UptimeRobot) + /api/vigilance (JSON public CORS *)
- Dockerfile multi-stage, CI Forgejo deploy.yml (pattern Reteno)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

astro.config.mjs

@@ -0,0 +1,16 @@
+import { defineConfig } from 'astro/config';
+import node from '@astrojs/node';
+import tailwind from '@astrojs/tailwind';
+
+export default defineConfig({
+  output: 'server',
+  adapter: node({ mode: 'standalone' }),
+  integrations: [tailwind({ applyBaseStyles: false })],
+  server: { host: '0.0.0.0', port: 4321 },
+  site: 'https://info-canicule.nocleus.com',
+  vite: {
+    ssr: {
+      noExternal: ['ioredis'],
+    },
+  },
+});