feat(monitor): activity log with rebuild polling + warm cache details

- Rebuild: shows webhook status, then polls every 15s until PMTiles
  last-modified changes, then shows success with new size/timestamp
- Warm cache: shows HIT/MISS/error breakdown after completion
- Activity log panel with timestamps, color-coded status, scrollable
- 15-minute timeout on rebuild polling

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

src/app/api/geoportal/monitor/route.ts

@@ -135,6 +135,21 @@ export async function GET() {
   return NextResponse.json(result);
 }
 
+async function getPmtilesInfo(): Promise<{ size: string; lastModified: string } | null> {
+  if (!PMTILES_URL) return null;
+  try {
+    const res = await fetchWithTimeout(PMTILES_URL, 3000);
+    return {
+      size: res.headers.get("content-length")
+        ? `${(parseInt(res.headers.get("content-length") ?? "0", 10) / 1024 / 1024).toFixed(1)} MB`
+        : "unknown",
+      lastModified: res.headers.get("last-modified") ?? "unknown",
+    };
+  } catch {
+    return null;
+  }
+}
+
 export async function POST(request: NextRequest) {
   const body = await request.json() as { action?: string };
   const action = body.action;
@@ -143,8 +158,10 @@ export async function POST(request: NextRequest) {
     if (!N8N_WEBHOOK_URL) {
       return NextResponse.json({ error: "N8N_WEBHOOK_URL not configured" }, { status: 400 });
     }
+    // Get current PMTiles state before rebuild
+    const before = await getPmtilesInfo();
     try {
-      await fetch(N8N_WEBHOOK_URL, {
+      const webhookRes = await fetch(N8N_WEBHOOK_URL, {
         method: "POST",
         headers: { "Content-Type": "application/json" },
         body: JSON.stringify({
@@ -152,32 +169,68 @@ export async function POST(request: NextRequest) {
           timestamp: new Date().toISOString(),
         }),
       });
-      return NextResponse.json({ ok: true, message: "Rebuild triggered via N8N" });
+      return NextResponse.json({
+        ok: true,
+        action: "rebuild",
+        webhookStatus: webhookRes.status,
+        previousPmtiles: before,
+        message: `Webhook trimis la N8N (HTTP ${webhookRes.status}). Rebuild-ul ruleaza ~8 min. Urmareste PMTiles last-modified.`,
+      });
     } catch (err) {
       const msg = err instanceof Error ? err.message : String(err);
-      return NextResponse.json({ error: `Webhook failed: ${msg}` }, { status: 500 });
+      return NextResponse.json({ error: `Webhook esuat: ${msg}` }, { status: 500 });
     }
   }
 
+  if (action === "check-rebuild") {
+    // Check if PMTiles was updated since a given timestamp
+    const previousLastModified = (body as { previousLastModified?: string }).previousLastModified;
+    const current = await getPmtilesInfo();
+    const changed = !!current && !!previousLastModified && current.lastModified !== previousLastModified;
+    return NextResponse.json({
+      ok: true,
+      action: "check-rebuild",
+      current,
+      changed,
+      message: changed
+        ? `Rebuild finalizat! PMTiles actualizat: ${current?.size}, ${current?.lastModified}`
+        : "Rebuild in curs...",
+    });
+  }
+
   if (action === "warm-cache") {
-    // Warm cache from within the container (tile-cache is on same Docker network)
     const sources = ["gis_terenuri", "gis_cladiri"];
-    let warmed = 0;
+    let total = 0;
+    let hits = 0;
+    let misses = 0;
+    let errors = 0;
     const promises: Promise<void>[] = [];
     for (const source of sources) {
-      // Bucharest area z14
       for (let x = 9200; x <= 9210; x++) {
         for (let y = 5960; y <= 5970; y++) {
+          total++;
           promises.push(
             fetchWithTimeout(`${TILE_CACHE_INTERNAL}/${source}/14/${x}/${y}`, 30000)
-              .then(() => { warmed++; })
-              .catch(() => { /* noop */ }),
+              .then((res) => {
+                const cache = res.headers.get("x-cache-status") ?? "";
+                if (cache === "HIT") hits++;
+                else misses++;
+              })
+              .catch(() => { errors++; }),
           );
         }
       }
     }
     await Promise.all(promises);
-    return NextResponse.json({ ok: true, message: `Cache warmed: ${warmed} tiles` });
+    return NextResponse.json({
+      ok: true,
+      action: "warm-cache",
+      total,
+      hits,
+      misses,
+      errors,
+      message: `${total} tile-uri procesate: ${hits} HIT, ${misses} MISS (nou incarcate), ${errors} erori`,
+    });
   }
 
   return NextResponse.json({ error: "Unknown action" }, { status: 400 });