feat(geoportal): N8N webhook on sync completion + tile cache monitoring

- weekend-deep-sync.ts: fire webhook to N8N_WEBHOOK_URL after each sync cycle
  (N8N triggers tippecanoe PMTiles rebuild via SSH on host)
- nginx tile-cache: add stub_status at /status, custom log format with cache status
- Add tile-cache-stats.sh: shows HIT/MISS ratio, cache size, slow tiles
- docker-compose: add N8N_WEBHOOK_URL env var

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/modules/parcel-sync/services/weekend-deep-sync.ts

@@ -401,6 +401,8 @@ export async function runWeekendDeepSync(): Promise<void> {
     console.log(
       `[weekend-sync] Ciclu complet #${state.completedCycles}! Reset pentru urmatorul ciclu.`,
     );
+    // Notify N8N to rebuild PMTiles (overview tiles for geoportal)
+    await fireSyncWebhook(state.completedCycles);
   }
 
   await saveState(state);
@@ -534,3 +536,28 @@ async function sendStatusEmail(
     console.warn(`[weekend-sync] Nu s-a putut trimite email: ${msg}`);
   }
 }
+
+/* ------------------------------------------------------------------ */
+/*  N8N Webhook — trigger PMTiles rebuild after sync cycle             */
+/* ------------------------------------------------------------------ */
+
+async function fireSyncWebhook(cycle: number): Promise<void> {
+  const url = process.env.N8N_WEBHOOK_URL;
+  if (!url) return;
+
+  try {
+    await fetch(url, {
+      method: "POST",
+      headers: { "Content-Type": "application/json" },
+      body: JSON.stringify({
+        event: "weekend-sync-cycle-complete",
+        cycle,
+        timestamp: new Date().toISOString(),
+      }),
+    });
+    console.log(`[weekend-sync] Webhook trimis la N8N (ciclu #${cycle})`);
+  } catch (err) {
+    const msg = err instanceof Error ? err.message : String(err);
+    console.warn(`[weekend-sync] Webhook N8N esuat: ${msg}`);
+  }
+}