Adds psalm and Nc style check.

.gitignore

+vendor
\ No newline at end of file

.php-cs-fixer.cache

+{"php":"7.3.33","version":"3.4.0:v3.4.0#47177af1cfb9dab5d1cc4daf91b7179c2efe7fad","indent":"\t","lineEnding":"\n","rules":{"encoding":true,"full_opening_tag":true,"blank_line_after_namespace":true,"braces":{"position_after_anonymous_constructs":"same","position_after_control_structures":"same","position_after_functions_and_oop_constructs":"same"},"class_definition":true,"constant_case":true,"elseif":true,"function_declaration":{"closure_function_spacing":"one"},"indentation_type":true,"line_ending":true,"lowercase_keywords":true,"method_argument_space":{"on_multiline":"ignore"},"no_break_comment":true,"no_closing_tag":true,"no_space_around_double_colon":true,"no_spaces_after_function_name":true,"no_spaces_inside_parenthesis":true,"no_trailing_whitespace":true,"no_trailing_whitespace_in_comment":true,"single_blank_line_at_eof":true,"single_class_element_per_statement":true,"single_import_per_statement":true,"single_line_after_imports":true,"switch_case_semicolon_to_colon":true,"switch_case_space":true,"visibility_required":{"elements":["property","method","const"]},"align_multiline_comment":true,"array_indentation":true,"binary_operator_spaces":{"default":"single_space"},"blank_line_after_opening_tag":true,"no_unused_imports":true},"hashes":{"appinfo\/routes.php":3044887257,"lib\/Responses\/SCIMJSONResponse.php":2876810868,"lib\/Responses\/SCIMListResponse.php":76345573,"lib\/Responses\/SCIMErrorResponse.php":1118832559,"lib\/Controller\/ASCIMGroup.php":3712028548,"lib\/Controller\/UserController.php":2528458696,"lib\/Controller\/ASCIMUser.php":430477040,"lib\/Controller\/GroupController.php":3769468563}}
\ No newline at end of file

.php-cs-fixer.dist.php

+<?php
+
+declare(strict_types=1);
+
+require_once './vendor/autoload.php';
+
+use Nextcloud\CodingStandard\Config;
+
+$config = new Config();
+$config
+	->getFinder()
+	->ignoreVCSIgnored(true)
+	->notPath('build')
+	->notPath('l10n')
+	->notPath('src')
+	->notPath('vendor')
+	->in(__DIR__);
+return $config;
\ No newline at end of file

composer.json

+{
+    "require-dev": {
+        "vimeo/psalm": "^4.23",
+        "christophwurst/nextcloud": "v22.1.1",
+        "nextcloud/coding-standard": "^1.0"
+    },
+    "config": {
+        "allow-plugins": {
+            "composer/package-versions-deprecated": true
+        }
+    },
+    "scripts": {
+        "cs:check": "php-cs-fixer fix --dry-run --diff",
+        "cs:fix": "php-cs-fixer fix"
+    }
+}

psalm.xml

+<?xml version="1.0"?>
+<psalm
+    errorLevel="4"
+    resolveFromConfigFile="true"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xmlns="https://getpsalm.org/schema/config"
+    xsi:schemaLocation="https://getpsalm.org/schema/config"
+>
+    <projectFiles>
+        <directory name="lib" />
+        <ignoreFiles>
+            <directory name="vendor" />
+        </ignoreFiles>
+    </projectFiles>
+    <extraFiles>
+        <directory name="vendor" />
+    </extraFiles>
+	<issueHandlers>
+		<UndefinedClass>
+			<errorLevel type="suppress">
+				<referencedClass name="OC" />
+                <referencedClass name="OC\Group\Manager" />
+				<referencedClass name="OC\Security\CSP\ContentSecurityPolicyNonceManager" />
+				<referencedClass name="Psr\Http\Client\ClientExceptionInterface" />
+			</errorLevel>
+		</UndefinedClass>
+		<UndefinedDocblockClass>
+			<errorLevel type="suppress">
+				<referencedClass name="Doctrine\DBAL\Driver\Statement" />
+				<referencedClass name="Doctrine\DBAL\Schema\Schema" />
+				<referencedClass name="Doctrine\DBAL\Schema\SchemaException" />
+				<referencedClass name="Doctrine\DBAL\Schema\Table" />
+				<referencedClass name="OC\Security\CSP\ContentSecurityPolicyNonceManager" />
+                <referencedClass name="OC\Group\Manager" />
+			</errorLevel>
+		</UndefinedDocblockClass>
+        <UndefinedInterfaceMethod>
+            <errorLevel type="suppress">
+				<referencedMethod name="OCP\IUser::getSystemEMailAddress" />
+            </errorLevel>
+        </UndefinedInterfaceMethod>
+	</issueHandlers>
+</psalm>
\ No newline at end of file