Add runtime filter, kid-friendly toggle, surprise me, and re-roll

- Runtime quick-select buttons (Any/90m/2h/2.5h) filter movies by length
- Kid-friendly toggle forces PG-13 max and boosts Family/Animation genres
- Surprise Me picks a random mood prompt from 20 curated options
- Show Me More re-rolls same mood excluding already-shown movies
- Re-roll appends new results to the existing search history entry

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/models.py

@@ -20,6 +20,10 @@ class Movie(BaseModel):
 class MoodRequest(BaseModel):
     mood: str
     additional_user_ids: list[str] = []
+    max_runtime: int | None = None  # Max runtime in minutes (None = no limit)
+    kid_friendly: bool = False  # Force PG-13 max rating + boost family genres
+    exclude_ids: list[str] = []  # Jellyfin IDs to exclude (for re-roll)
+    history_id: int | None = None  # If set, append results to this history entry
 
 
 class Recommendation(BaseModel):