Add explicit aggregation methods for metrics (#15480)

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Co-authored-by: Alex Krawiec <[email protected]>

Author: coolguyzone

docs/product/explore/metrics/index.mdx

@@ -35,6 +35,8 @@ Sentry supports three types of metrics:
 
 Counters track how many times something happened. Each increment adds to a cumulative total.
 
+**Aggregation methods**: `sum`, `per_second`, and `per_minute`.
+
 **Use cases**: events that occur over time
 - `email.sent` - Track total emails sent
 - `checkout.failed` - Track failed checkout attempts
@@ -44,14 +46,18 @@ Counters track how many times something happened. Each increment adds to a cumul
 
 Gauges set a specific value at a point in time, like a snapshot. The latest value replaces the previous one.
 
+**Aggregation methods**: `min`, `max`, `avg`, `per_second`, and `per_minute`.
+
 **Use cases**: current state or level
 - `queue.depth` - Current number of items in queue
 - `pool.in_use` - Active connections in a pool
 - `memory.usage` - Current memory consumption
 
 ### Distributions
 
-Distributions record numeric values to compute statistical aggregates like p50, p95, average, and sum.
+Distributions record numeric values to compute statistical aggregates.
+
+**Aggregation methods**: `p50`, `p75`, `p95`, `p99`, `avg`, `sum`, `min`, `max`, `count`, `per_second`, and `per_minute`. 
 
 **Use cases**: values that vary and need statistical analysis
 - `cart.amount_usd` - Purchase amounts for revenue tracking