feat(coderd): add coder_app usage stats (#9001)

Updates #8658

coderd/database/queries/workspaceappstats.sql

@@ -0,0 +1,37 @@
+-- name: InsertWorkspaceAppStats :exec
+INSERT INTO
+	workspace_app_stats (
+		user_id,
+		workspace_id,
+		agent_id,
+		access_method,
+		slug_or_port,
+		session_id,
+		session_started_at,
+		session_ended_at,
+		requests
+	)
+SELECT
+	unnest(@user_id::uuid[]) AS user_id,
+	unnest(@workspace_id::uuid[]) AS workspace_id,
+	unnest(@agent_id::uuid[]) AS agent_id,
+	unnest(@access_method::text[]) AS access_method,
+	unnest(@slug_or_port::text[]) AS slug_or_port,
+	unnest(@session_id::uuid[]) AS session_id,
+	unnest(@session_started_at::timestamptz[]) AS session_started_at,
+	unnest(@session_ended_at::timestamptz[]) AS session_ended_at,
+	unnest(@requests::int[]) AS requests
+ON CONFLICT
+	(user_id, agent_id, session_id)
+DO
+	UPDATE SET
+		session_ended_at = EXCLUDED.session_ended_at,
+		requests = EXCLUDED.requests
+	WHERE
+		workspace_app_stats.user_id = EXCLUDED.user_id
+		AND workspace_app_stats.agent_id = EXCLUDED.agent_id
+		AND workspace_app_stats.session_id = EXCLUDED.session_id
+		-- Since stats are updated in place as time progresses, we only
+		-- want to update this row if it's fresh.
+		AND workspace_app_stats.session_ended_at <= EXCLUDED.session_ended_at
+		AND workspace_app_stats.requests <= EXCLUDED.requests;