refactor(probe): consolidate full probe() into MediaProber port

Add probe(video) -> MediaInfo | None to the MediaProber Protocol and
implement it on FfprobeMediaProber. The standalone
alfred/infrastructure/filesystem/ffprobe.py module is removed; all
callers (analyze_release / probe_media tools, testing scripts) now go
through the adapter.

Tests for the probe path moved to tests/infrastructure/test_ffprobe_prober.py
(patching subprocess.run at the adapter module level).

Unblocks the upcoming inspect_release orchestrator, which needs the
port — not a free function — to compose parse + main-video selection
+ probe in one shot.

testing/recognize_folders_in_downloads.py

@@ -103,8 +103,10 @@ def main() -> None:
     from alfred.application.filesystem.detect_media_type import detect_media_type
     from alfred.application.filesystem.enrich_from_probe import enrich_from_probe
     from alfred.domain.release.services import parse_release
-    from alfred.infrastructure.filesystem.ffprobe import probe
     from alfred.infrastructure.filesystem.find_video import find_video_file
+    from alfred.infrastructure.probe import FfprobeMediaProber
+
+    _prober = FfprobeMediaProber()
 
     entries = sorted(downloads.iterdir(), key=lambda p: p.name.lower())
     total = len(entries)
@@ -126,7 +128,7 @@ def main() -> None:
             if p.media_type not in ("unknown", "other"):
                 video_file = find_video_file(entry)
                 if video_file:
-                    media_info = probe(video_file)
+                    media_info = _prober.probe(video_file)
                     if media_info:
                         enrich_from_probe(p, media_info)
             warnings = _assess(p)