Show MetaInstance sharding/type while PLACING, fix MlxIbv references

When a MetaInstance has no backing instance yet, derive the strategy
display from the MetaInstance's own sharding and instanceMeta fields
rather than showing "Unknown (Unknown)".

Also clean up all stale MlxIbv references across the dashboard —
the backend enum is MlxJaccl.

Co-Authored-By: Claude Opus 4.6 <[email protected]>

dashboard/src/routes/+page.svelte

@@ -84,13 +84,6 @@
     errorMessage: null,
   } as const;
 
-  const UNKNOWN_INSTANCE_INFO = {
-    instanceType: "Unknown",
-    sharding: "Unknown",
-    nodeNames: [] as string[],
-    nodeIds: [] as string[],
-    nodeCount: 0,
-  } as const;
   const tbBridgeData = $derived(nodeThunderboltBridge());
   const identitiesData = $derived(nodeIdentities());
   const tbIdentifiers = $derived(nodeThunderbolt());
@@ -1728,6 +1721,8 @@
     instance: unknown | null; // The backing/orphan instance (tagged union) or null if placing
     instanceId: string | null; // The actual Instance ID (for topology hover)
     isMetaInstance: boolean;
+    sharding: string | null; // From MetaInstance constraints (used when instance is null)
+    instanceMeta: string | null; // From MetaInstance constraints (used when instance is null)
   }
 
   const unifiedDisplayItems = $derived((): DisplayItem[] => {
@@ -1741,6 +1736,8 @@
         instance: backingId ? instanceData[backingId] : null,
         instanceId: backingId,
         isMetaInstance: true,
+        sharding: meta.sharding,
+        instanceMeta: meta.instanceMeta,
       });
     }
     // Orphan Instances
@@ -1752,6 +1749,8 @@
         instance: inst,
         instanceId: orphanId,
         isMetaInstance: false,
+        sharding: null,
+        instanceMeta: null,
       });
     }
     return items;
@@ -2444,7 +2443,13 @@
                   {@const instanceModelId = item.modelId}
                   {@const instanceInfo = instance
                     ? getInstanceInfo(instance)
-                    : UNKNOWN_INSTANCE_INFO}
+                    : {
+                        instanceType: item.instanceMeta === "MlxRing" ? "MLX Ring" : item.instanceMeta === "MlxJaccl" ? "MLX RDMA" : "Unknown",
+                        sharding: item.sharding ?? "Unknown",
+                        nodeNames: [] as string[],
+                        nodeIds: [] as string[],
+                        nodeCount: 0,
+                      }}
                   {@const instanceConnections = instance
                     ? getInstanceConnections(instance)
                     : []}
@@ -3269,7 +3274,13 @@
                     {@const instanceModelId = item.modelId}
                     {@const instanceInfo = instance
                       ? getInstanceInfo(instance)
-                      : UNKNOWN_INSTANCE_INFO}
+                      : {
+                          instanceType: item.instanceMeta === "MlxRing" ? "MLX Ring" : item.instanceMeta === "MlxJaccl" ? "MLX RDMA" : "Unknown",
+                          sharding: item.sharding ?? "Unknown",
+                          nodeNames: [] as string[],
+                          nodeIds: [] as string[],
+                          nodeCount: 0,
+                        }}
                     {@const instanceConnections = instance
                       ? getInstanceConnections(instance)
                       : []}