Plugin framework updates (#3535)

* refactor entrypoint into helpers

* Add lookup by metadata
This is geared towards plugins packaged in pkgs that differ in name from their top module

* Make module lookup predictable in changing pkg-envs

* remove no coverage from plugin packages

* ignore coverage for production loadin

* refactor plugin collection - move assigment out

* do not cover fs errors

* test custom dir loading

* test module meta fetcher

* add a bit more safety

* do not cover sanity checkers

* add folder loading test

* ignore again for cleaner diffs for now

* ignore safety catch

* rename test

* Add test for package installs

* fix docstring name

* depreciate test for now

* Fix for out of BASE_DIR paths

* ignore catch

* remove unneeded complexity

* add testing for outside folders

* more docstrings and simpler methods

* make call simpler

* refactor import

* Add registry with all plugins

* use full registry and make simpler request

* switch path properties to methods

* Add typing to plugin

* Add a checker fnc for is_sample

* Add sample check to admin page

* Make file check a cls

* more cls methods

* Add setting for signature cheks
Fixes #3520

* make property statements simpler

* use same key in all dicts

* Use module name instead of NAME
Fixes #3534

* fix naming

* fix name

* add version checking
Fixes #3478

* fix formatting and typing

* also save reference to full array

* do not cover as we turn on all plugins

* add test for check_version

* Add version e2e test

* make test save

* refactor out assignment

* safe a db reference first

* docstring

* condense code a bit

* rename

* append logging

* rename

* also safe db reference to new object

* docstrings, refactors, typing

* fix key lookup

InvenTree/common/models.py

@@ -1268,6 +1268,13 @@ class InvenTreeSetting(BaseInvenTreeSetting):
             'requires_restart': True,
         },
 
+        'PLUGIN_CHECK_SIGNATURES': {
+            'name': _('Check plugin signatures'),
+            'description': _('Check and show signatures for plugins'),
+            'default': False,
+            'validator': bool,
+        },
+
         # Settings for plugin mixin features
         'ENABLE_PLUGINS_URL': {
             'name': _('Enable URL integration'),