Expect use of some of MD_STD's wrappers over default functions

More are to follow.

rules/phpstan-rules.neon

@@ -42,6 +42,28 @@ parameters:
             - MDMysqliExpectedError
             - MDgenericInvalidInputsException
             - MDExpectedException
+    disallowedFunctionCalls:
+        -
+            function: 'file_get_contents()'
+            message: 'use MD_STD::file_get_contents() instead'
+        -
+            function: 'realpath()'
+            message: 'use MD_STD::realpath() instead'
+        -
+            function: 'unlink()'
+            message: 'use MD_STD::unlink() instead'
+        -
+            function: 'scandir()'
+            message: 'use MD_STD::scandir() instead'
+        -
+            function: 'move_uploaded_file()'
+            message: 'use MD_STD_IN::move_uploaded_file() instead'
+        -
+            function: 'mkdir()'
+            message: 'use MD_STD_IN::mkdir() instead'
+        -
+            function: 'MD_STD::startsWith()'
+            message: 'use str_starts_with() instead'
 
 parametersSchema:
     ergebnis: structure([