fix: make docker compose build and start the API

The image context was backend/, so COPY frontend/ failed. Build from the
repo root, place Python modules on the import path, and pin packages that
exist on PyPI. The web process no longer loads the LLM at startup.

backend/app/utils/schedule_manager.py

@@ -0,0 +1,77 @@
+import json
+import os
+from datetime import datetime
+from typing import List, Dict, Optional
+
+class ScheduleManager:
+    def __init__(self, schedules_path: str = "/app/schedules.json"):
+        self.schedules_path = schedules_path
+        self.schedules = self._load_schedules()
+
+    def _load_schedules(self) -> List[Dict]:
+        """Load schedules from JSON file."""
+        if os.path.exists(self.schedules_path):
+            try:
+                with open(self.schedules_path, 'r') as f:
+                    return json.load(f)
+            except json.JSONDecodeError:
+                return []
+        return []
+
+    def save_schedules(self):
+        """Save schedules to JSON file."""
+        os.makedirs(os.path.dirname(self.schedules_path), exist_ok=True)
+        with open(self.schedules_path, 'w') as f:
+            json.dump(self.schedules, f, indent=2)
+
+    def add_schedule(self, schedule: Dict) -> Dict:
+        """Add a new schedule."""
+        schedule_id = max([s['id'] for s in self.schedules], default=0) + 1
+        new_schedule = {
+            'id': schedule_id,
+            'time': schedule['time'],
+            'book': schedule.get('book'),
+            'enabled': schedule.get('enabled', True),
+        }
+        self.schedules.append(new_schedule)
+        self.save_schedules()
+        return new_schedule
+
+    def update_schedule(self, schedule_id: int, updates: Dict) -> Optional[Dict]:
+        """Update an existing schedule."""
+        for i, schedule in enumerate(self.schedules):
+            if schedule['id'] == schedule_id:
+                self.schedules[i].update(updates)
+                self.save_schedules()
+                return self.schedules[i]
+        return None
+
+    def delete_schedule(self, schedule_id: int) -> bool:
+        """Delete a schedule."""
+        for i, schedule in enumerate(self.schedules):
+            if schedule['id'] == schedule_id:
+                self.schedules.pop(i)
+                self.save_schedules()
+                return True
+        return False
+
+    def get_schedule(self, schedule_id: int) -> Optional[Dict]:
+        """Get a specific schedule."""
+        for schedule in self.schedules:
+            if schedule['id'] == schedule_id:
+                return schedule
+        return None
+
+    def list_schedules(self) -> List[Dict]:
+        """List all schedules."""
+        return self.schedules
+
+    def get_enabled_schedules(self) -> List[Dict]:
+        """Get all enabled schedules."""
+        return [s for s in self.schedules if s.get('enabled', True)]
+
+    def is_schedule_ready(self, schedule: Dict) -> bool:
+        """Check if a schedule is ready to be sent."""
+        schedule_time = datetime.fromisoformat(schedule['time'].replace('Z', '+00:00'))
+        current_time = datetime.now()
+        return current_time >= schedule_time