feat: add network calls column to AI sessions table (#27269)

Add a "Total/blocked network calls" column to the AIBridge sessions
table.

Update `ListAIBridgeSessions` query to calculate network called made and
blocked per session. See query plan
[here](https://explain.dalibo.com/plan/54355c90b165ggb4).

---------

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

coderd/database/modelqueries.go

@@ -1054,6 +1054,9 @@ func (q *sqlQuerier) ListAuthorizedAIBridgeSessions(ctx context.Context, arg Lis
 			&i.CacheWriteInputTokens,
 			&i.LastPrompt,
 			&i.LastActiveAt,
+			&i.NetworkCallsTotal,
+			&i.NetworkCallsBlocked,
+			&i.FirewallActive,
 		); err != nil {
 			return nil, err
 		}