(docs) show daily metrics tab

docs/my-website/docs/proxy/metrics.md

@@ -0,0 +1,32 @@
+# 💸 GET Daily Spend, Usage Metrics
+
+## Response format 
+```json
+[
+    {
+        "daily_spend": 7.9261938052047e+16,
+        "day": "2024-02-01T00:00:00",
+        "spend_per_model": {"azure/gpt-4": 7.9261938052047e+16},
+        "spend_per_api_key": {
+            "76": 914495704992000.0,
+            "12": 905726697912000.0,
+            "71": 866312628003000.0,
+            "28": 865461799332000.0,
+            "13": 859151538396000.0
+        }
+    },
+    {
+        "daily_spend": 7.938489251309491e+16,
+        "day": "2024-02-02T00:00:00",
+        "spend_per_model": {"gpt-3.5": 7.938489251309491e+16},
+        "spend_per_api_key": {
+            "91": 896805036036000.0,
+            "78": 889692646082000.0,
+            "49": 885386687861000.0,
+            "28": 873869890984000.0,
+            "56": 867398637692000.0
+        }
+    }
+]
+
+```

docs/my-website/sidebars.js

@@ -40,6 +40,7 @@ const sidebars = {
         "proxy/virtual_keys",
         "proxy/users",
         "proxy/ui",
+        "proxy/metrics",
         "proxy/model_management",
         "proxy/health",
         "proxy/debugging",