refactor(release): move detect_media_type & enrich_from_probe to application/release

Both helpers are inspection-pipeline pieces, not filesystem use cases —
they belong next to inspect_release, not next to move_media /
resolve_destination / list_folder.

The move also kills the lazy import that was hiding inside
_resolve_parsed: alfred.application.filesystem.resolve_destination
no longer triggers a cycle through alfred.application.filesystem
__init__ when loading inspect_release. Top-level import restored.

Call sites updated: inspect.py, test_detect_media_type.py,
test_enrich_from_probe.py, testing/recognize_folders_in_downloads.py.
Module docstrings + test-file docstrings updated to match the new
location.

CHANGELOG.md

@@ -15,6 +15,19 @@ callers).
 
 ## [Unreleased]
 
+### Internal
+
+- **Moved `detect_media_type` and `enrich_from_probe` from
+  `alfred.application.filesystem` to `alfred.application.release`**.
+  They are inspection-pipeline helpers — their natural home is next to
+  `inspect_release`, not next to the filesystem use cases. The move
+  also eliminates a circular-import workaround in
+  `resolve_destination.py`: `inspect_release` can now be imported at
+  module top instead of lazily inside `_resolve_parsed`. Public
+  surface is unchanged for callers that imported the helpers from
+  their full module paths (the only call sites — `inspect.py`, two
+  tests, one testing script — were updated in this commit).
+
 ### Added
 
 - **`resolve_*_destination` use cases now consume `inspect_release`**.