feat: add activities API routes and register in api.py

New endpoints:
- GET /activities — full data (normal + evil)
- GET /activities/{section}/{mood} — per-mood activities
- POST /activities/{section}/{mood} — update activities with validation
- POST /activities/reload — force reload from disk

bot/routes/activities.py

@@ -0,0 +1,73 @@
+"""Activities API routes — CRUD for mood-based song/game activity lists."""
+
+from fastapi import APIRouter, Request
+from fastapi.responses import JSONResponse
+from utils.logger import get_logger
+
+logger = get_logger('api')
+
+router = APIRouter()
+
+
+@router.get("/activities")
+def get_all_activities():
+    """Return the full activities data (normal + evil sections, all moods)."""
+    from utils.activities import get_all_activities
+    return get_all_activities()
+
+
+@router.get("/activities/{section}/{mood}")
+def get_mood_activities(section: str, mood: str):
+    """Return activities for a specific mood.
+    
+    Args:
+        section: "normal" or "evil"
+        mood: mood name (e.g. "bubbly", "aggressive")
+    """
+    if section not in ("normal", "evil"):
+        return JSONResponse(status_code=400, content={"error": "Section must be 'normal' or 'evil'"})
+
+    from utils.activities import get_activities_for_mood
+    activities = get_activities_for_mood(mood, is_evil=(section == "evil"))
+    return {"section": section, "mood": mood, "activities": activities}
+
+
+@router.post("/activities/{section}/{mood}")
+async def set_mood_activities(section: str, mood: str, request: Request):
+    """Update activities for a specific mood.
+    
+    Body: {"activities": [{"type": "listening"|"playing", "name": "...", "weight": 1}]}
+    """
+    if section not in ("normal", "evil"):
+        return JSONResponse(status_code=400, content={"error": "Section must be 'normal' or 'evil'"})
+
+    data = await request.json()
+    activities = data.get("activities")
+
+    if activities is None:
+        return JSONResponse(status_code=400, content={"error": "Request body must include 'activities' list"})
+
+    if not isinstance(activities, list):
+        return JSONResponse(status_code=400, content={"error": "'activities' must be a list"})
+
+    try:
+        from utils.activities import set_activities_for_mood
+        set_activities_for_mood(mood, is_evil=(section == "evil"), activities=activities)
+        logger.info(f"Updated activities for {section}/{mood}: {len(activities)} entries")
+        return {"status": "ok", "section": section, "mood": mood, "count": len(activities)}
+    except ValueError as e:
+        return JSONResponse(status_code=400, content={"error": str(e)})
+    except Exception as e:
+        logger.error(f"Failed to save activities for {section}/{mood}: {e}")
+        return JSONResponse(status_code=500, content={"error": "Internal server error"})
+
+
+@router.post("/activities/reload")
+def reload_activities():
+    """Force reload activities from disk (useful after hand-editing the YAML)."""
+    from utils.activities import _load_activities
+    data = _load_activities(force=True)
+    normal_count = sum(len(v) for v in data.get("normal", {}).values())
+    evil_count = sum(len(v) for v in data.get("evil", {}).values())
+    logger.info(f"Force-reloaded activities: {normal_count} normal entries, {evil_count} evil entries")
+    return {"status": "ok", "normal_entries": normal_count, "evil_entries": evil_count}