Degrade gracefully on overlay/audio failure; notify on upload success

Sunrise:
- Overlay failure no longer exits 1; the speed-only video is renamed to the
  expected final path so OnSuccess still fires and the upload still happens
- sunrise2mm.py now notifies on every upload outcome (success, post failure,
  file-not-found) via notify.sh so the user always knows whether the video
  reached Mattermost

Montage:
- Music+overlay failure no longer exits 1; the sped video is promoted to the
  *-Montage.mp4 path so year-end-join can still include this movement (as a
  silent, no-overlay clip) and the user is notified of the degraded output
- Year-end join trigger is now outside the success/failure branch so it fires
  in both cases

https://claude.ai/code/session_01C4jbd3waXG3eKZYbGUjLUQ

daily_sunrise_video.sh

@@ -140,22 +140,23 @@ DT="${DT}:x=w-tw-18:y=(h-th)/2"
 DT="${DT}:shadowcolor=black@0.55:shadowx=1:shadowy=1"
 
 # ── Step 3: Overlay — sunrise time burned in ──────────────────────────────────
-# If this fails, $sped_video survives at its permanent path for manual recovery.
+# If overlay fails, the sped video is promoted to the upload target so
+# OnSuccess still fires and the upload happens (without timestamp overlay).
 final_video="$output_dir/$current_date-daily-sunrise.mp4"
 echo "Step 3/3: overlay → $final_video"
-if ! ffmpeg -loglevel warning \
+if ffmpeg -loglevel warning \
     -i "$sped_video" \
     -vf "${DT}" \
     -c:v libx264 -pix_fmt yuv420p -crf "$CRF_SUNRISE" -an \
     -y "$final_video"; then
-    "$SCRIPT_DIR/notify.sh" "FAILED: sunrise overlay $current_date" \
-        "Overlay failed — speed-only video saved: $(basename "$sped_video")" || true
-    exit 1
+    actual_dur=$(ffprobe -v error -show_entries format=duration -of csv=p=0 "$final_video")
+    echo "Done: $final_video  (${actual_dur}s, sunrise at ${SR_TIME})"
+    rm -f "$sped_video"
+    "$SCRIPT_DIR/notify.sh" "Sunrise ready: $current_date" \
+        "$(basename "$final_video") — ${actual_dur}s, sunrise at ${SR_TIME}" || true
+else
+    mv "$sped_video" "$final_video"
+    echo "Overlay failed — promoting speed-only video as upload target"
+    "$SCRIPT_DIR/notify.sh" "WARNING: sunrise overlay failed $current_date" \
+        "Overlay step failed — uploading speed-only video (no timestamp)" || true
 fi
-
-actual_dur=$(ffprobe -v error -show_entries format=duration -of csv=p=0 "$final_video")
-echo "Done: $final_video  (${actual_dur}s, sunrise at ${SR_TIME})"
-
-rm -f "$sped_video"
-"$SCRIPT_DIR/notify.sh" "Sunrise ready: $current_date" \
-    "$(basename "$final_video") — ${actual_dur}s, sunrise at ${SR_TIME}" || true