chore: populate connectionlog count using a separate query (#18629)

This is the third PR for moving connection events out of the audit log.

This PR populates `count` on `ConnectionLogResponse` using a separate query, to preemptively mitigate the issue described in #17689. It's structurally identical to a portion of https://github.com/coder/coder/pull/18600, but for the connection log instead of the audit log.
       
Future PRs:
- Implement a table in the Web UI for viewing connection logs.
- Write a query to delete old events from the audit log, call it from dbpurge.
- Write documentation for the endpoint / feature

coderd/database/modelqueries.go

@@ -614,6 +614,7 @@ func (q *sqlQuerier) CountAuthorizedAuditLogs(ctx context.Context, arg CountAudi
 
 type connectionLogQuerier interface {
 	GetAuthorizedConnectionLogsOffset(ctx context.Context, arg GetConnectionLogsOffsetParams, prepared rbac.PreparedAuthorized) ([]GetConnectionLogsOffsetRow, error)
+	CountAuthorizedConnectionLogs(ctx context.Context, arg CountConnectionLogsParams, prepared rbac.PreparedAuthorized) (int64, error)
 }
 
 func (q *sqlQuerier) GetAuthorizedConnectionLogsOffset(ctx context.Context, arg GetConnectionLogsOffsetParams, prepared rbac.PreparedAuthorized) ([]GetConnectionLogsOffsetRow, error) {
@@ -700,6 +701,53 @@ func (q *sqlQuerier) GetAuthorizedConnectionLogsOffset(ctx context.Context, arg
 	return items, nil
 }
 
+func (q *sqlQuerier) CountAuthorizedConnectionLogs(ctx context.Context, arg CountConnectionLogsParams, prepared rbac.PreparedAuthorized) (int64, error) {
+	authorizedFilter, err := prepared.CompileToSQL(ctx, regosql.ConvertConfig{
+		VariableConverter: regosql.ConnectionLogConverter(),
+	})
+	if err != nil {
+		return 0, xerrors.Errorf("compile authorized filter: %w", err)
+	}
+	filtered, err := insertAuthorizedFilter(countConnectionLogs, fmt.Sprintf(" AND %s", authorizedFilter))
+	if err != nil {
+		return 0, xerrors.Errorf("insert authorized filter: %w", err)
+	}
+
+	query := fmt.Sprintf("-- name: CountAuthorizedConnectionLogs :one\n%s", filtered)
+	rows, err := q.db.QueryContext(ctx, query,
+		arg.OrganizationID,
+		arg.WorkspaceOwner,
+		arg.WorkspaceOwnerID,
+		arg.WorkspaceOwnerEmail,
+		arg.Type,
+		arg.UserID,
+		arg.Username,
+		arg.UserEmail,
+		arg.ConnectedAfter,
+		arg.ConnectedBefore,
+		arg.WorkspaceID,
+		arg.ConnectionID,
+		arg.Status,
+	)
+	if err != nil {
+		return 0, err
+	}
+	defer rows.Close()
+	var count int64
+	for rows.Next() {
+		if err := rows.Scan(&count); err != nil {
+			return 0, err
+		}
+	}
+	if err := rows.Close(); err != nil {
+		return 0, err
+	}
+	if err := rows.Err(); err != nil {
+		return 0, err
+	}
+	return count, nil
+}
+
 func insertAuthorizedFilter(query string, replaceWith string) (string, error) {
 	if !strings.Contains(query, authorizedQueryPlaceholder) {
 		return "", xerrors.Errorf("query does not contain authorized replace string, this is not an authorized query")