Add option to specify a default filter either by config or by function

[kaystrobach]

This will allow to build a set of facets and their default values once the query is generated the first time

[kaystrobach]

This is possible in the repo for now.

example

    /**
     * @param Query $queryObject
     * @param string $searchName
     * @return array
     * @throws \Neos\Flow\Persistence\Exception\InvalidQueryException
     */
    public function initializeFindByQuery($queryObject, $searchName)
    {
        if (($searchName !== 'ssoPersonsForTeachers') && ($searchName !== 'ssoPersonsForTeachersDeprecated')) {
            return [];
        }

        $account = $this->authenticationManager->getSecurityContext()->getAccount();
        if (!($account instanceof Account)) {
            throw new InvalidArgumentException('No account found in security context');
        }
        /** @var Person $party */
        $party = $this->partyService->getAssignedPartyOfAccount($account);

        $now = new DateTime();

        return [
            $queryObject->logicalAnd(
                [
                    // hide expired accounts
                    $queryObject->logicalOr(
                        [
                            $queryObject->equals('accounts.expirationDate', null),
                            $queryObject->greaterThanOrEqual('accounts.expirationDate', $now)
                        ]
                    ),
                    // institutionen
                    $queryObject->logicalOr(
                        $this->getInstitutionDemands($party, $queryObject)
                    )
                ]
            )
        ];
    }