Sunrise time overlay; systemd upload separation; bug fixes

daily_sunrise_video.sh:
- Fixed: was using undefined \$MOVIES_DIR (now \$BASE_DIR/movies)
- Fixed: sunrise_overlay.py was called but never existed — would fail daily
- Fixed: speed-adjust step had no explicit codec (-c:v libx264 missing)
- New: sunrise time overlaid as stacked vertical characters on the right
  side using ffmpeg drawtext — no Python/Pillow dependency
- New: upload removed from script; now triggered by systemd OnSuccess=
- Combines speed-adjust and overlay into one ffmpeg pass (was two)
- SUNRISE_OVERLAY_OPACITY from conf controls transparency

install.sh:
- sky-cam-sunrise.service gains OnSuccess=sky-cam-sunrise-upload.service
  so upload only runs when video creation succeeds, with separate log
- New sky-cam-sunrise-upload.service runs sunrise2mm.py

sunrise2mm.py: add shebang + chmod +x so systemd ExecStart= calls it directly

sky-cam.conf: add SUNRISE_OVERLAY_OPACITY=0.45

https://claude.ai/code/session_01C4jbd3waXG3eKZYbGUjLUQ

sunrise2mm.py

@@ -1,3 +1,4 @@
+#!/usr/bin/env python3
 import requests
 import os
 from datetime import datetime