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.

alfred/agent/tools/filesystem.py

@@ -28,10 +28,12 @@ from alfred.application.filesystem.resolve_destination import (
     resolve_series_destination as _resolve_series_destination,
 )
 from alfred.infrastructure.filesystem import FileManager, create_folder, move
-from alfred.infrastructure.filesystem.ffprobe import probe
 from alfred.infrastructure.filesystem.find_video import find_video_file
 from alfred.infrastructure.metadata import MetadataStore
 from alfred.infrastructure.persistence import get_memory
+from alfred.infrastructure.probe import FfprobeMediaProber
+
+_PROBER = FfprobeMediaProber()
 
 _LEARNED_ROOT = Path(_alfred_pkg.__file__).parent.parent / "data" / "knowledge"
 
@@ -201,7 +203,7 @@ def analyze_release(release_name: str, source_path: str) -> dict[str, Any]:
     if parsed.media_type not in ("unknown", "other"):
         video_file = find_video_file(path, _KB)
         if video_file:
-            media_info = probe(video_file)
+            media_info = _PROBER.probe(video_file)
             if media_info:
                 enrich_from_probe(parsed, media_info)
                 probe_used = True
@@ -241,7 +243,7 @@ def probe_media(source_path: str) -> dict[str, Any]:
             "message": f"{source_path} does not exist",
         }
 
-    media_info = probe(path)
+    media_info = _PROBER.probe(path)
     if media_info is None:
         return {
             "status": "error",