ui: fix avg token/sec calculation on models page (#357)

* ui: use percentiles for token stats
* ui: add histogram of metrics
* update vite to remove security warnings

fixes #355

ui/package-lock.json

@@ -3975,9 +3975,9 @@
       }
     },
     "node_modules/vite": {
-      "version": "6.3.5",
-      "resolved": "https://registry.npmjs.org/vite/-/vite-6.3.5.tgz",
-      "integrity": "sha512-cZn6NDFE7wdTpINgs++ZJ4N49W2vRp8LCKrn3Ob1kYNtOo21vfDoaV5GzBfLU4MovSAB8uNRm4jgzVQZ+mBzPQ==",
+      "version": "6.4.1",
+      "resolved": "https://registry.npmjs.org/vite/-/vite-6.4.1.tgz",
+      "integrity": "sha512-+Oxm7q9hDoLMyJOYfUYBuHQo+dkAloi33apOPP56pzj+vsdJDzr+j1NISE5pyaAuKL4A3UD34qd0lx5+kfKp2g==",
       "dev": true,
       "license": "MIT",
       "dependencies": {