Fix corrupt-file detection in make-finals.sh

The previous check used || true which masked ffprobe's non-zero exit
code.  For files with a missing/partial moov atom ffprobe can print a
duration estimate then exit non-zero — the || true let that through.

Now use || raw_dur="" to honour the exit code, and add a second probe
for an actual video stream codec so files that report a duration but
have no decodable stream are also caught.

https://claude.ai/code/session_01C4jbd3waXG3eKZYbGUjLUQ

make-finals.sh

@@ -110,8 +110,10 @@ while IFS= read -r -d '' temp_file; do
         continue
     fi
 
-    raw_dur=$(ffprobe -v error -show_entries format=duration -of csv=p=0 "$temp_file" 2>/dev/null || true)
-    if [ -z "$raw_dur" ] || [ "$raw_dur" = "N/A" ]; then
+    raw_dur=$(ffprobe -v error -show_entries format=duration -of csv=p=0 "$temp_file" 2>/dev/null) || raw_dur=""
+    vid_codec=$(ffprobe -v error -select_streams v:0 -show_entries stream=codec_name \
+        -of csv=p=0 "$temp_file" 2>/dev/null) || vid_codec=""
+    if [ -z "$raw_dur" ] || [ "$raw_dur" = "N/A" ] || [ -z "$vid_codec" ]; then
         echo "SKIP (corrupt/unreadable): $temp_file"
         (( skipped++ )) || true
         continue