* Fix: redirect SHARE_LINK_BUNDLE_DIR to the test temp layout instead of the real media directory
* Fix: include f_to in test_filters subTest labels so each of the 8 cases reports distinctly
* Fix: run the post_consume error-log assertion after the raising call and match the actual paperless_mail logger name
* Fix: rename the blank-password workflow test to match its behavior and add a real wrong-password-fails test
* Fix: use the created social account's actual pk and remove an accidental tuple wrapping the mock provider
* Fix: assert against the created documents' actual pks instead of hardcoded 1 and 2
* Fix: assert test_compression actually produces a valid LZMA-compressed zip
* Fix: clear os.environ when patching PAPERLESS_ADMIN_* vars so a host-set value can't leak into the no-user test
* Fix: restore MIDDLEWARE, AUTHENTICATION_BACKENDS and REST_FRAMEWORK auth classes after each remote-user settings test instead of leaking the mutation into later tests
* Fix: use a guaranteed-nonexistent temp path instead of hardcoded /tmp/foo/bar in test_export_target_not_exists
The unittest side of the suite built its temp directory tree with
tempfile.mkdtemp and a manually enabled override_settings, cleaned up only if
tearDown ran. That is now gone. DirectoriesMixin lives alongside the layout it
bridges and does nothing but hand the paperless_dirs fixture to TestCase
subclasses as self.dirs, so both halves of the suite get the same twelve
settings, the same directory shapes and cleanup owned by tmp_path.
The mixin moves to paperless_testing.dirs rather than staying in the documents
test utilities, because modules in paperless and paperless_mail import it
across the app boundary. The thirty-eight consuming modules change only their
import line; self.dirs.scratch_dir and its siblings keep working.