feat(auth): track unique tools in access metrics

* Add tool tracking to AccessTracker and metrics
* Update tests to validate tool tracking functionality
* Modify middleware to record tool usage
* Enhance observability with tool context
* Update UI to display unique tools in metrics

ui/src/components/dashboard/DashboardPage.svelte

@@ -50,7 +50,7 @@
 {/if}
 
 {#if data}
-  <div class="mt-6 grid gap-6 xl:grid-cols-2">
+  <div class="mt-6 grid gap-6 xl:grid-cols-3">
     <ConnectionBreakdown
       title="Requests By IP Address"
       entries={data.metrics.top_ips}
@@ -61,5 +61,10 @@
       entries={data.metrics.top_agents}
       emptyLabel="No user agents recorded yet."
     />
+    <ConnectionBreakdown
+      title="Requests By MCP Tool"
+      entries={data.metrics.top_tools}
+      emptyLabel="No MCP tool calls recorded yet."
+    />
   </div>
 {/if}

ui/src/components/dashboard/StatusCards.svelte

@@ -4,7 +4,7 @@
   const { data }: { data: StatusResponse } = $props();
 </script>
 
-<div class="mt-6 grid gap-4 sm:grid-cols-2 xl:grid-cols-3">
+<div class="mt-6 grid gap-4 sm:grid-cols-2 xl:grid-cols-4">
   <div class="rounded-2xl border border-white/10 bg-white/5 p-5">
     <p class="text-sm uppercase tracking-[0.2em] text-slate-400">Connected users</p>
     <p class="mt-2 text-3xl font-semibold text-white">{data.connected_count}</p>
@@ -25,6 +25,10 @@
     <p class="text-sm uppercase tracking-[0.2em] text-slate-400">Unique agents</p>
     <p class="mt-2 text-3xl font-semibold text-white">{data.metrics.unique_agents}</p>
   </div>
+  <div class="rounded-2xl border border-white/10 bg-white/5 p-5">
+    <p class="text-sm uppercase tracking-[0.2em] text-slate-400">Unique MCP tools</p>
+    <p class="mt-2 text-3xl font-semibold text-white">{data.metrics.unique_tools}</p>
+  </div>
   <div class="rounded-2xl border border-white/10 bg-white/5 p-5">
     <p class="text-sm uppercase tracking-[0.2em] text-slate-400">Version</p>
     <p class="mt-2 break-all text-2xl font-semibold text-white">{data.version}</p>