feat(video): add streamable video events & dashboard controls

Add end-to-end support for video events: server streaming, scheduler
metadata, API fields, and dashboard UI.

- Server: range-capable streaming endpoint with byte-range support.
- Scheduler: emits `video` object; best-effort HEAD probe adds
  `mime_type`, `size`, `accept_ranges`; placeholders for richer
  metadata (duration/resolution/bitrate/qualities/thumbnails).
- API/DB: accept and persist `event_media_id`, `autoplay`, `loop`,
  `volume` for video events.
- Frontend: Event modal supports video selection + playback options;
  FileManager increased upload size and client-side duration check
  (max 10 minutes).
- Docs/UX: bumped program-info, added UX-only changelog and updated
  Copilot instructions for contributors.
- Notes: metadata extraction (ffprobe), checksum persistence, and
  HLS/DASH transcoding are recommended follow-ups (separate changes).

scheduler/db_utils.py

@@ -7,6 +7,7 @@ from sqlalchemy.orm import sessionmaker, joinedload
 from sqlalchemy import create_engine, or_, and_, text
 from models.models import Event, EventMedia, EventException
 from dateutil.rrule import rrulestr
+from urllib.request import Request, urlopen
 from datetime import timezone
 
 # Load .env only in development to mirror server/database.py behavior
@@ -256,6 +257,56 @@ def format_event_with_media(event):
                     f"[Scheduler] Using website URL for event_media_id={media.id} (type={event.event_type.value}): {media.url}")
                 _media_decision_logged.add(media.id)
 
-        # Add other event types (video, message, etc.) here as needed...
+        # Handle video events
+        elif event.event_type.value == "video":
+            filename = os.path.basename(media.file_path) if media.file_path else "video"
+            # Use streaming endpoint for better video playback support
+            stream_url = f"{API_BASE_URL}/api/eventmedia/stream/{media.id}/{filename}"
+
+            # Best-effort: probe the streaming endpoint for cheap metadata (HEAD request)
+            mime_type = None
+            size = None
+            accept_ranges = False
+            try:
+                req = Request(stream_url, method='HEAD')
+                with urlopen(req, timeout=2) as resp:
+                    # getheader returns None if missing
+                    mime_type = resp.getheader('Content-Type')
+                    length = resp.getheader('Content-Length')
+                    if length:
+                        try:
+                            size = int(length)
+                        except Exception:
+                            size = None
+                    accept_ranges = (resp.getheader('Accept-Ranges') or '').lower() == 'bytes'
+            except Exception as e:
+                # Don't fail the scheduler for probe errors; log once per media
+                if media.id not in _media_decision_logged:
+                    logging.debug(f"[Scheduler] HEAD probe for media_id={media.id} failed: {e}")
+
+            event_dict["video"] = {
+                "type": "media",
+                "url": stream_url,
+                "autoplay": getattr(event, "autoplay", True),
+                "loop": getattr(event, "loop", False),
+                "volume": getattr(event, "volume", 0.8),
+                # Best-effort metadata to help clients decide how to stream
+                "mime_type": mime_type,
+                "size": size,
+                "accept_ranges": accept_ranges,
+                # Optional richer info (may be null if not available): duration (seconds), resolution, bitrate
+                "duration": None,
+                "resolution": None,
+                "bitrate": None,
+                "qualities": [],
+                "thumbnails": [],
+                "checksum": None,
+            }
+            if media.id not in _media_decision_logged:
+                logging.debug(
+                    f"[Scheduler] Using video streaming URL for event_media_id={media.id}: {filename}")
+                _media_decision_logged.add(media.id)
+
+        # Add other event types (message, etc.) here as needed...
 
     return event_dict