Stuck. Help is needed :) I need to get this (example with interaction):

docker exec -i -u nobody php_pk /bin/sh -c "XDEBUG_MOD=off PHP_CS_FIXER_IGNORE_ENV=1 /var/www/bin/php-cs-fixer fix --dry-run --verbose --format json -"
PHP needs to be a minimum version of PHP 7.4.0 and maximum version of PHP 8.1.*.
Current PHP version: 8.2.10.
Ignoring environment requirements because `PHP_CS_FIXER_IGNORE_ENV` is set. Execution may be unstable.
PHP CS Fixer 3.9.5 Grand Awaiting by Fabien Potencier and Dariusz Ruminski.
PHP runtime: 8.2.10
Loaded config default from "/var/www/.php-cs-fixer.php".
Using cache file ".php-cs-fixer.cache".
<?php echo ("dss");
{"files":[{"name":"php:\/\/stdin","appliedFixers":["no_unneeded_control_parentheses","blank_line_after_opening_tag","single_quote"]}],"time":{"total":29.961},"memory":16}%  

but in phpactor I get

[2023-10-04 04:36:10] phpactor.DEBUG: Executed '/usr/bin/docker' 'exec' '-i' '-u' 'nobody' 'php_pk' '/bin/sh' '-c' '"XDEBUG_MODE=off PHP_CS_FIXER_IGNORE_ENV=1 /var/www/bin/php-cs-fixer fix --dry-run --verbose --format json -"', which exited with 127 {"channel":"php-cs-fixer"} []
[2023-10-04 04:36:10] phpactor.ERROR: Diagnostic provider "php-cs-fixer" errored with "php-cs-fixer exited with code '127'; cmd: '/usr/bin/docker' 'exec' '-i' '-u' 'nobody' 'php_pk' '/bin/sh' '-c' '"XDEBUG_MODE=off PHP_CS_FIXER_IGNORE_ENV=1 /var/www/bin/php-cs-fixer fix --dry-run --verbose --format json -;"'; stderr: '/bin/sh: 1: XDEBUG_MODE=off PHP_CS_FIXER_IGNORE_ENV=1 /var/www/bin/php-cs-fixer fix --dry-run --verbose --format json -;: not found '; stdout: ''", removing from pool {"channel":"LSPDIAG"

found issue. proc_open sh command should not be escaped with "" 🎉

i'm not convinced this is the right way to approach this. the "wrapper" concept applies to all linters that need to call out to docker-container. it would be better to run Phpactor in the same enviornment as the project (especially as some features such as enums are only enabled when the runtime is f.e. 8.1)

additionally it is better to specify the wrapper ['as', 'an', 'array', 'of', 'arguments'] as this removes any ambiguity caused by quoting.

would it be possible to install multiple versions of PHP on your o/s or distribution? e.g. I had php7.4, php8.0, php8.1 on debian, and on NixOS I can basically choose.

As I said before and in the description: this covers the case when phpactor can't be used in same container. I had some thoughts about to have second container with same php version for phpactor only and include project source.
About wrapper command. It seems not so much differents as it doesn't have any quotes at all and in the result it is same array.
I use Arch. It can have different versions of php, but mainly I develop in containers, so it is not so important and project can be in different version as main machine.

although what problem is this solving? i also run many dockerised projects with various requirements, and running the tooling with my globally installed version of PHP (8.1) is fine

The problem is php-cs-fixer. It can't be in different versions during checks, because then cache file will be rebuilt and this takes time (from 10 seconds to 5-6 minutes). So, the problem is not directly for phpactor but for the tools around it. I'll give a try to figure out how to use phpactor in another container and how to deal with vim/mason installation but I'm not sure how to deal per project. This patch works for me and I don't need to deal with more complexity but if it is wrong way how to solve my issue then I need to align with the main vision of phpactor