fix(intake): regenerate API contracts and tighten the metrics endpoint

Addresses review findings on #1374.

P1 — the generated contracts were missing the new surface, failing CI's
Lint all. Regenerated OpenAPI, the Python SDK via Stainless, the vendored
CLI, and the web SDK. The traces resource now exposes `get_metrics`, and
`Trace` carries agent_id / agent_name / agent_version.

Stainless placed the new endpoint as a top-level `trace_metrics`
standalone API with a `reviewme_list` method. Per the resolve-reviewme
guidance, a single-method resource folds into its parent, so it lives on
the existing intake `traces` resource as `get_metrics`; the path and
schemas are untouched.

P3 — the metrics endpoint accepted page, page_size and sort through the
shared list validator and silently ignored them, implying a paginated
response where every bucket in the range is returned. It now validates
against its own parameter set, so `?page=999` is a 400 rather than a
misleading 200.

P3 — the span rollup CTE filtered only on trace_id, so a trace_id shared
across ingest formats pulled in unrelated spans before the join discarded
them. Restrict by (source_format, trace_id) as the page-refs variant and
the join already do. trace_id is kept in the predicate to drive the bloom
filter. Verified the figures are unchanged against live ClickHouse.

Signed-off-by: mschwab <mschwab@nvidia.com>

Author: marcusds

docs/cli/reference.mdx

@@ -6811,7 +6811,7 @@ nemo intake ingest spans create [OPTIONS]
 **Options:**
 
 * `--workspace`
-* `--source`: (required)
+* `--source`: Stable name for the source trace store, such as `langsmith` or `mlflow`.
 * `--spans`: JSON string
 
 **Help:**
@@ -7103,9 +7103,49 @@ nemo intake traces [OPTIONS] COMMAND [ARGS]...
 
 **Commands:**
 
+* `get-metrics`: Get Trace Metrics
 * `list`: List Traces
 * `get`: Get Trace
 
+##### nemo intake traces get-metrics
+
+Get Trace Metrics
+
+**Usage:**
+
+```shell
+nemo intake traces get-metrics [OPTIONS]
+```
+
+**Options:**
+
+* `--workspace`
+* `--bucket <CHOICE>`: Time bucket granularity. [possible values: total, day, week, month]
+* `--timezone`: IANA timezone the buckets are aligned to, e.g. America/Los_Angeles.
+
+**Filter Options:**
+
+* `--filter FILTER_JSON`: Use --filter with JSON for complex/nested queries, or --filter. FIELD options for simple fields. Both can be combined, with field options taking precedence.
+JSON-only fields:
+  started_at: \{gte: str, lte: str}
+
+Filter the traces the metrics are computed over. Accepts the same fields as the traces list, so agent_id or agent_name scopes the rollup to one agent.
+* `--filter.id`
+* `--filter.agent-id`
+* `--filter.agent-name`
+* `--filter.evaluation-id`
+* `--filter.session-id`
+* `--filter.status`
+* `--filter.test-case-id`
+
+**Help:**
+
+* `--help, -h`: Show this message and exit.
+
+**Output Options:**
+
+* `--output-format, --output, -f <CHOICE>`: Output format for an entity. [possible values: json, yaml, raw, code]
+
 ##### nemo intake traces list
 
 List Traces
@@ -7133,6 +7173,8 @@ JSON-only fields:
 
 Filter root-span-backed traces by id, session_id, root status, root span started_at, evaluation_id, and test_case_id.
 * `--filter.id`
+* `--filter.agent-id`
+* `--filter.agent-name`
 * `--filter.evaluation-id`
 * `--filter.session-id`
 * `--filter.status`