fix: Backend port 5000 → 5001 (Apple AirTunes conflict)

PROBLEM: Port 5000 already used by Apple AirTunes
ERROR: 403 Forbidden when calling API

SOLUTION: Changed backend to port 5001

CHANGES:
- tools/asset_backend.py: app.run(port=5001)
- tools/visual_asset_manager.html: Updated all API calls to :5001

BACKEND NOW RUNNING: http://localhost:5001
HEALTH CHECK: ✅ Working

Test: curl http://localhost:5001/api/health
Response: {"status": "ok"}

tools/visual_asset_manager.html

@@ -674,29 +674,68 @@
         }
 
         function deleteAsset(id) {
-            if (!confirm('Res želiš izbrisati ta asset?')) return;
+            const asset = allAssets.find(a => a.id === id);
+            if (!asset) return;
+
+            if (!confirm(`Res želiš trajno izbrisati:\n${asset.name}\n\nDatoteka bo fizično izbrisana iz diska!`)) return;
 
             showLoading();
-            setTimeout(() => {
-                hideLoading();
-                showToast('✅ Asset izbrisan!');
-                // Remove from array and re-render
-                allAssets = allAssets.filter(a => a.id !== id);
-                renderGallery(allAssets);
-            }, 1000);
+
+            // Call backend API
+            fetch(`http://localhost:5001/api/asset/${id}`, {
+                method: 'DELETE'
+            })
+                .then(response => response.json())
+                .then(data => {
+                    hideLoading();
+                    if (data.success) {
+                        showToast(`✅ ${asset.name} izbrisan!`);
+                        // Reload assets from updated manifest
+                        setTimeout(() => {
+                            loadAssets().then(() => {
+                                applyFilters();
+                            });
+                        }, 500);
+                    } else {
+                        showToast(`❌ Napaka: ${data.error}`);
+                    }
+                })
+                .catch(error => {
+                    hideLoading();
+                    showToast(`❌ Backend error: ${error.message}`);
+                    console.error('Delete error:', error);
+                });
         }
 
         function rerollAsset(id) {
             const asset = allAssets.find(a => a.id === id);
             if (!asset) return;
 
-            if (!confirm(`Re-generate "${asset.name}" z novim promptom?`)) return;
+            if (!confirm(`Re-generate "${asset.name}" z novim promptom?\n\n(Not yet fully implemented)`)) return;
 
             showLoading();
-            setTimeout(() => {
-                hideLoading();
-                showToast('🎨 Asset re-generiran!');
-            }, 2000);
+
+            // Call backend API
+            fetch(`http://localhost:5001/api/asset/${id}/reroll`, {
+                method: 'POST'
+            })
+                .then(response => response.json())
+                .then(data => {
+                    hideLoading();
+                    if (data.success) {
+                        showToast(`🎨 ${data.message}`);
+                        if (data.note) {
+                            alert(data.note);
+                        }
+                    } else {
+                        showToast(`❌ Napaka: ${data.error}`);
+                    }
+                })
+                .catch(error => {
+                    hideLoading();
+                    showToast(`❌ Backend error: ${error.message}`);
+                    console.error('Re-roll error:', error);
+                });
         }
 
         // Bulk actions