Homepages nur weiß mit Http Error 500 nach Paket Installation

[der Schwede]

A) Nach einer fehlgeschlagenen Installation von der Erweiterung contao-changelanguage (terminal42), in einer aktiven Contao-Installation 4.4.47 (mit einem Rocksolid Theme, gehostet bei All-Inkl), sind meine Homepages alle nur weiß, bzw. liefern ein Http Error 500. Ich komme nicht ins Contao Backend rein.

Der Sprachenwechsler ist im Contao Manager NICHT als installiertes Paket gelistet.

Gestern die komplette Datenbank zurückgespielt, aber das Problem verbleibt. Ich habe (dummerweise) keine komplette Sicherung der gesamten Ordnerstruktur / Dateien (der Contao-Installation).

Zustand jetzt: der Contao Manager startet mit dem Hinweis

„Systemwiederherstellung Es wurden Dateien erkannt, die nach einer Contao-Installation aussehen, aber die Kommandozeile scheint nicht korrekt zu funktionieren. Wählen Sie eine Option, um das System zu reparieren. Automatische Reparatur“ ….

Nach Start im Abgesicherten Modus und Systemwartung / Composer Abhängigkeiten installiere, kommt diese Fehlermeldung:

Warning: in_array() expects parameter 2 to be array, null given in /www/xxxxxxxx/!polajannhov/vendor/contao/core-bundle/src/Resources/contao/library/Contao/System.php on line 164
PHP Warning:  in_array() expects parameter 2 to be array, null given in /www/htdocs/xxxxxx/!polajannhov/vendor/contao/core-bundle/src/Resources/contao/library/Contao/System.php on line 164
19:49:55 ERROR     [console] Error thrown while running command "cache:warmup --env=prod". Message: "Class 'Haste\Dca\DateRangeFilter' not found" ["exception" => Error { …},"command" => "cache:warmup --env=prod","message" => "Class 'Haste\Dca\DateRangeFilter' not found"]
In System.php line 170:
  
  Attempted to load class "DateRangeFilter" from namespace "Haste\Dca".  
  Did you forget a "use" statement for another namespace?                

cache:warmup [--no-optional-warmers] [-h|--help] [-q|--quiet] [-v|vv|vvv|--verbose] [-V|--version] [--ansi] [--no-ansi] [-n|--no-interaction] [-e|--env ENV] [--no-debug] [--] <command>

Loading composer repositories with package information
Installing dependencies from lock file
Nothing to install or update
Package oyejorge/less.php is abandoned, you should avoid using it. No replacement was suggested.
Generating optimized autoload files
> Contao\ManagerBundle\Composer\ScriptHandler::initializeApplication
Script Contao\ManagerBundle\Composer\ScriptHandler::initializeApplication handling the post-install-cmd event terminated with an exception

In ScriptHandler.php line 113:
                
  An error occurred while executing the "cache:warmup" command: PHP Warning:   
   in_array() expects parameter 2 to be array, null given in /www/htdocs/w00d  
  8185/!polajannhov/vendor/contao/core-bundle/src/Resources/contao/library/Co  
  ntao/System.php on line 164                                                  
  19:49:55 ERROR     [console] Error thrown while running command "cache:warm  
  up --env=prod". Message: "Class 'Haste\Dca\DateRangeFilter' not found" ["ex  
  ception" => Error { …},"command" => "cache:warmup --env=prod","message" =>   
  "Class 'Haste\Dca\DateRangeFilter' not found"]                               
                                                                               
  In System.php line 170:      
    Attempted to load class "DateRangeFilter" from namespace "Haste\Dca".      
    Did you forget a "use" statement for another namespace?                    
   
       cache:warmup [--no-optional-warmers] [-h|--help] [-q|--quiet] [-v|vv|vvv|--  
  verbose] [-V|--version] [--ansi] [--no-ansi] [-n|--no-interaction] [-e|--en  
  v ENV] [--no-debug] [--] <command>                                           
                                                                               
install [--prefer-source] [--prefer-dist] [--dry-run] [--dev] [--no-dev] [--no-custom-installers] [--no-autoloader] [--no-scripts] [--no-progress] [--no-suggest] [-v|vv|vvv|--verbose] [-o|--optimize-autoloader] [-a|--classmap-authoritative] [--apcu-autoloader] [--ignore-platform-reqs] [--] [<packages>...]
# Process terminated with exit code 1
# Result: General error
### Der Hintergrundprozess wurde unerwartet beendet ###

A der Stelle komme ich nicht weiter, und hoffe auf guten Rat.
Ich habe auch einen anderen Rettungs-Versuche unternommen, Postings B) unten.
Freue mich auf Hinweise was zu tun sein könnte.

[der Schwede]

B) Nach Systemwartung / Composer Abhängigkeiten installiere (wie Posting oben), startet der Contao Manager sauber.
Ich habe dann versucht der Sprachenwechsler erneut zu installieren. Der Testlauf läuft sauber, aber die tatsächliche Paket-Installation endet mit dieser Fehlermeldung:

In AbstractModuleInstaller.php line 582: 
Installation target "/www/htdocs/xxxxxx/!polajannhov/system/modules/multi columnwizard" already exists install [--prefer-source] [--prefer-dist] [--dry-run] [--dev] [--no-dev] [--no-custom-installers] [--no-autoloader] [--no-scripts] [--no-progress] [--no-suggest] [-v|vv|vvv|--verbose] [-o|--optimize-autoloader] [-a|--classmap-authoritative] [--apcu-autoloader] [--ignore-platform-reqs] [--] [<packages>...] 
# Process terminated with exit code 1 
# Result: General error

Worauf ich den Schritt Abgesichter Modus / Systemwartung / Composer Abhängigkeiten installiere wiederholen muss.
Jetzt diese Fehlermeldung:

$ /usr/bin/php71 -q -d memory_limit=-1 /www/htdocs/xxxxxx/!polajannhov/web/contao-manager.phar.php composer install --prefer-dist --no-dev --no-progress --no-suggest --no-ansi --no-interaction --optimize-autoloader
contao/manager-plugin: Generating plugin class...
contao/manager-plugin: ...done generating plugin class
Loading composer repositories with package information
Installing dependencies from lock file
Nothing to install or update
Package oyejorge/less.php is abandoned, you should avoid using it. No replacement was suggested.
Generating optimized autoload files
> Contao\ManagerBundle\Composer\ScriptHandler::initializeApplication
InvalidArgumentException: Config file "/www/htdocs/xxxxxx/!polajannhov/contao-manager/composer-install.set.json" does not exist. in phar:///www/htdocs/xxxxxx/!polajannhov/web/contao-manager.phar.php/api/Process/AbstractProcess.php:56
Stack trace:
#0 phar:///www/htdocs/xxxxxx/!polajannhov/web/contao-manager.phar.php/api/Process/ProcessRunner.php(185): Contao\ManagerApi\Process\AbstractProcess::readConfig('/www/htdocs/w00...')
#1 phar:///www/htdocs/xxxxxx/!polajannhov/web/contao-manager.phar.php/api/Process/ProcessRunner.php(116): Contao\ManagerApi\Process\ProcessRunner->loadConfig()
#2 phar:///www/htdocs/xxxxxx/!polajannhov/web/contao-manager.phar.php/api/Process/ProcessRunner.php(61): Contao\ManagerApi\Process\ProcessRunner->wait(1)
#3 phar:///www/htdocs/xxxxxx/!polajannhov/web/contao-manager.phar.php/api/Command/ProcessRunnerCommand.php(46): Contao\ManagerApi\Process\ProcessRunner->run()
#4 phar:///www/htdocs/xxxxxx/!polajannhov/web/contao-manager.phar.php/vendor/symfony/console/Command/Command.php(255): Contao\ManagerApi\Command\ProcessRunnerCommand->execute(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#5 phar:///www/htdocs/xxxxxx/!polajannhov/web/contao-manager.phar.php/vendor/symfony/console/Application.php(1030): Symfony\Component\Console\Command\Command->run(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#6 phar:///www/htdocs/xxxxxx/!polajannhov/web/contao-manager.phar.php/vendor/symfony/console/Application.php(272): Symfony\Component\Console\Application->doRunCommand(Object(Contao\ManagerApi\Command\ProcessRunnerCommand), Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#7 phar:///www/htdocs/xxxxxx/!polajannhov/web/contao-manager.phar.php/api/ApiApplication.php(70): Symfony\Component\Console\Application->doRun(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#8 phar:///www/htdocs/xxxxxx/!polajannhov/web/contao-manager.phar.php/vendor/symfony/console/Application.php(148): Contao\ManagerApi\ApiApplication->doRun(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#9 phar:///www/htdocs/xxxxxx/!polajannhov/web/contao-manager.phar.php/api/console(86): Symfony\Component\Console\Application->run(Object(Symfony\Component\Console\Input\ArgvInput))
#10 /www/htdocs/xxxxxx/!polajannhov/web/contao-manager.phar.php(57): require('phar:///www/htd...')
#11 {main}
# Process terminated with exit code 143
# Result: Termination (request to terminate) [signal 15]
## Der Hintergrundprozess wurde unerwartet beendet ###

Da weis ich nicht was Sinvoll sein könnte ...
und habe aber danach wieder einen sauberen Start des C.-Managers.
Darauf habe ich die Ordner
- changelanguage,
- haste und
- multicolumnwizard (in system / modules) umbenannt,
und die Paket-Installation vom Sprachenwechsler wiederholt.
Testlauf erneut ok, aber die Paket-Installation endet mit:

$ /usr/bin/php71 -q -d memory_limit=-1 /www/htdocs/xxxxxx/!polajannhov/web/contao-manager.phar.php composer require terminal42/contao-changelanguage --no-suggest --no-update --no-scripts --prefer-stable --sort-packages --no-ansi --no-interaction

Using version ^3.1 for terminal42/contao-changelanguage
/www/htdocs/xxxxxx/!polajannhov/composer.json has been updated

# Process terminated with exit code 0
# Result: OK

> Resolving dependencies using Composer Cloud v2.2.4
# Job ID HNwC2jleqqg0TL0axW1j7uxpx5s7nH1rWq4ilKQbfhANG7WrSoBltC6bAwyC5zSFCpx8G0qT9cGoXQKzrvnrDrRVen0vnEprsxBNhlv3RdJ57RZGUvOmhD9SQ0J completed in 50 seconds
# Memory usage: 426.34MB (peak: 2306.68MB), time: 50.93s.
$ /usr/bin/php71 -q -d memory_limit=-1 /www/htdocs/xxxxxx/!polajannhov/web/contao-manager.phar.php composer install --prefer-dist --no-dev --no-progress --no-suggest --no-ansi --no-interaction --optimize-autoloader
contao/manager-plugin: Generating plugin class...
contao/manager-plugin: ..done generating plugin class
 // Clearing the cache for the prod environment with debug                      
 // false                                                                       
 [OK] Cache for the "prod" environment (debug=false) was successfully cleared.  
 // Warming up the cache for the prod environment with debug                    
 // false                                                                       

PHP Fatal error:  Cannot declare class Haste\Dca\DateRangeFilter, because the name is already in use in /www/htdocs/xxxxxx/!polajannhov/var/cache/prod/contao/dca/DateRangeFilter.php on line 16

Fatal error: Cannot declare class Haste\Dca\DateRangeFilter, because the name is already in use in /www/htdocs/xxxxxx/!polajannhov/var/cache/prod/contao/dca/DateRangeFilter.php on line 16

In DateRangeFilter.php line 16:
                         
  Compile Error: Cannot declare class Haste\Dca\DateRangeFilter, because the   
  name is already in use  
cache:warmup [--no-optional-warmers] [-h|--help] [-q|--quiet] [-v|vv|vvv|--verbose] [-V|--version] [--ansi] [--no-ansi] [-n|--no-interaction] [-e|--env ENV] [--no-debug] [--] <command>

Loading composer repositories with package information
Installing dependencies from lock file
Package operations: 4 installs, 0 updates, 0 removals
  - Installing contao-community-alliance/composer-plugin (3.0.9): Loading from cache
  - Installing menatwork/contao-multicolumnwizard (3.3.16): Loading from cache
  - Installing codefog/contao-haste (4.24.5): Loading from cache
  - Installing terminal42/contao-changelanguage (3.1.13): Loading from cache
Package oyejorge/less.php is abandoned, you should avoid using it. No replacement was suggested.
Generating optimized autoload files
> Contao\ManagerBundle\Composer\ScriptHandler::initializeApplication
Script Contao\ManagerBundle\Composer\ScriptHandler::initializeApplication handling the post-install-cmd event terminated with an exception

In ScriptHandler.php line 113:
      An error occurred while executing the "cache:warmup" command: PHP Fatal error:  Cannot declare class Haste\Dca\DateRangeFilter, because the name is al  
  ready in use in /www/htdocs/xxxxxx/!polajannhov/var/cache/prod/contao/dca  
  /DateRangeFilter.php on line 16                                              
                  
  In DateRangeFilter.php line 16:
    Compile Error: Cannot declare class Haste\Dca\DateRangeFilter, because the name is already in use cache:warmup [--no-optional-warmers] [-h|--help] [-q|--quiet] [-v|vv|vvv|--  
  verbose] [-V|--version] [--ansi] [--no-ansi] [-n|--no-interaction] [-e|--en  
  v ENV] [--no-debug] [--] <command>                                           
                                                                               

install [--prefer-source] [--prefer-dist] [--dry-run] [--dev] [--no-dev] [--no-custom-installers] [--no-autoloader] [--no-scripts] [--no-progress] [--no-suggest] [-v|vv|vvv|--verbose] [-o|--optimize-autoloader] [-a|--classmap-authoritative] [--apcu-autoloader] [--ignore-platform-reqs] [--] [<packages>...]


# Process terminated with exit code 1
# Result: General error
### Der Hintergrundprozess wurde unerwartet beendet ###

Auch das sagt mir nichts, wie ich weiter vorgehen könnte, um meine Sites wieder online zu bekommen.
Ich habe auch den Rettungs-Versuch wie am Anfang oben A) versucht.
Freue mich auf Hinweise was zu tun sein könnte.