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

sunrise2mm.py

@@ -1,6 +1,7 @@
 #!/usr/bin/env python3
 import requests
 import os
+import subprocess
 from datetime import datetime
 
 import pathlib
@@ -91,9 +92,33 @@ if os.path.isfile(final_video_file):
 
         if message_response.status_code == 201:
             print("Message posted successfully.")
+            subprocess.run(
+                [str(_here / 'notify.sh'),
+                 f"Sunrise uploaded: {today_date_str}",
+                 f"Video posted to Mattermost successfully"],
+                check=False
+            )
         else:
             print(f"Failed to post message: {message_response.text}")
+            subprocess.run(
+                [str(_here / 'notify.sh'),
+                 f"FAILED: sunrise Mattermost post {today_date_str}",
+                 f"File uploaded but post failed: {message_response.status_code}"],
+                check=False
+            )
     else:
         print(f"Failed to upload {final_video_file}: {response.text}")
+        subprocess.run(
+            [str(_here / 'notify.sh'),
+             f"FAILED: sunrise upload {today_date_str}",
+             f"Mattermost file upload failed: {response.status_code}"],
+            check=False
+        )
 else:
     print(f"No video file found at {final_video_file}.")
+    subprocess.run(
+        [str(_here / 'notify.sh'),
+         f"FAILED: sunrise upload {today_date_str}",
+         f"Video file not found: {final_video_file}"],
+        check=False
+    )