Add Prometheus telemetry for token generation and system metrics

.gitignore

@@ -25,3 +25,5 @@ erl_crash.dump
 # Ignore package tarball (built via "mix hex.build").
 graphql_api_assignment-*.tar
 
+.cursor/
+

config/config.exs

@@ -23,6 +23,13 @@ config :ecto_shorts,
 config :graphql_api_assignment,
   generators: [timestamp_type: :utc_datetime]
 
+config :prometheus_telemetry,
+  default_millisecond_buckets: [100, 300, 500, 1000, 2000, 5000, 10_000],
+  default_microsecond_buckets: [50_000, 100_000, 250_000, 500_000, 750_000],
+  measurement_poll_period: :timer.seconds(10),
+  ecto_max_query_length: 150,
+  ecto_known_query_module: nil
+
 # Configures the endpoint
 config :graphql_api_assignment, GraphqlApiAssignmentWeb.Endpoint,
   url: [host: "localhost"],

grafana/custom/token_pipeline_export.json

@@ -0,0 +1,209 @@
+{
+    "annotations": {
+      "list": [
+        {
+          "builtIn": 1,
+          "datasource": {
+            "type": "grafana",
+            "uid": "-- Grafana --"
+          },
+          "enable": true,
+          "hide": true,
+          "iconColor": "rgba(0, 211, 255, 1)",
+          "name": "Annotations & Alerts",
+          "type": "dashboard"
+        }
+      ]
+    },
+    "editable": true,
+    "fiscalYearStartMonth": 0,
+    "graphTooltip": 0,
+    "id": 3,
+    "links": [],
+    "panels": [
+      {
+        "datasource": {
+          "type": "prometheus",
+          "uid": "cedvl3fku3chsc"
+        },
+        "fieldConfig": {
+          "defaults": {
+            "color": {
+              "mode": "palette-classic"
+            },
+            "custom": {
+              "axisBorderShow": true,
+              "axisCenteredZero": false,
+              "axisColorMode": "text",
+              "axisLabel": "",
+              "axisPlacement": "auto",
+              "barAlignment": 0,
+              "barWidthFactor": 0.6,
+              "drawStyle": "line",
+              "fillOpacity": 0,
+              "gradientMode": "none",
+              "hideFrom": {
+                "legend": false,
+                "tooltip": false,
+                "viz": false
+              },
+              "insertNulls": false,
+              "lineInterpolation": "linear",
+              "lineWidth": 1,
+              "pointSize": 5,
+              "scaleDistribution": {
+                "type": "linear"
+              },
+              "showPoints": "auto",
+              "spanNulls": false,
+              "stacking": {
+                "group": "A",
+                "mode": "none"
+              },
+              "thresholdsStyle": {
+                "mode": "off"
+              }
+            },
+            "mappings": [],
+            "thresholds": {
+              "mode": "absolute",
+              "steps": [
+                {
+                  "color": "green",
+                  "value": null
+                },
+                {
+                  "color": "red",
+                  "value": 80
+                }
+              ]
+            }
+          },
+          "overrides": []
+        },
+        "gridPos": {
+          "h": 8,
+          "w": 12,
+          "x": 0,
+          "y": 0
+        },
+        "id": 2,
+        "options": {
+          "legend": {
+            "calcs": [
+              "sum"
+            ],
+            "displayMode": "table",
+            "placement": "right",
+            "showLegend": true
+          },
+          "tooltip": {
+            "hideZeros": false,
+            "mode": "single",
+            "sort": "none"
+          }
+        },
+        "pluginVersion": "11.5.1",
+        "targets": [
+          {
+            "datasource": {
+              "type": "prometheus",
+              "uid": "cedvl3fku3chsc"
+            },
+            "editorMode": "code",
+            "expr": "rate(grapql_api_token_generation_duration_millisecond_bucket[1m])",
+            "instant": false,
+            "legendFormat": "__auto",
+            "range": true,
+            "refId": "A"
+          }
+        ],
+        "title": "Token Generation Duration",
+        "type": "timeseries"
+      },
+      {
+        "datasource": {
+          "type": "prometheus",
+          "uid": "cedvl3fku3chsc"
+        },
+        "fieldConfig": {
+          "defaults": {
+            "color": {
+              "mode": "thresholds"
+            },
+            "mappings": [],
+            "thresholds": {
+              "mode": "absolute",
+              "steps": [
+                {
+                  "color": "green",
+                  "value": null
+                },
+                {
+                  "color": "red",
+                  "value": 80
+                }
+              ]
+            }
+          },
+          "overrides": []
+        },
+        "gridPos": {
+          "h": 8,
+          "w": 12,
+          "x": 12,
+          "y": 0
+        },
+        "id": 1,
+        "options": {
+          "minVizHeight": 75,
+          "minVizWidth": 75,
+          "orientation": "auto",
+          "reduceOptions": {
+            "calcs": [
+              "lastNotNull"
+            ],
+            "fields": "",
+            "values": false
+          },
+          "showThresholdLabels": false,
+          "showThresholdMarkers": true,
+          "sizing": "auto"
+        },
+        "pluginVersion": "11.5.1",
+        "targets": [
+          {
+            "datasource": {
+              "type": "prometheus",
+              "uid": "cedvl3fku3chsc"
+            },
+            "editorMode": "code",
+            "expr": "grapql_api_token_generation_total_count",
+            "instant": false,
+            "legendFormat": "__auto",
+            "range": true,
+            "refId": "A"
+          }
+        ],
+        "title": "Total Session Tokens Generated",
+        "type": "gauge"
+      }
+    ],
+    "preload": false,
+    "refresh": "",
+    "schemaVersion": 40,
+    "tags": [],
+    "templating": {
+      "list": []
+    },
+    "time": {
+      "from": "now-6h",
+      "to": "now"
+    },
+    "timepicker": {},
+    "timezone": "browser",
+    "title": "Token Pipeline",
+    "uid": "aedynclbhdg5cc",
+    "version": 2,
+    "weekStart": ""
+  }