Add support for decimal column type (#1739)

* Add support for `decimal` column type

Previously `decimal` columns were represented with a cast. This now is no longer the case and instead the column type itself is `decimal`. This change takes that into account.

* The column type may also be `numeric`

* Update tests

src/Console/ModelsCommand.php

@@ -584,6 +584,8 @@ class ModelsCommand extends Command
                     'float', 'real', 'float4',
                     'double', 'float8' => 'float',
 
+                    'decimal', 'numeric' => 'numeric',
+
                     default => 'string',
                 };
             }