Move slot expansion logic to ExchangeService

- Add get_available_slots() and _expand_availability_to_slots() to ExchangeService
- Update routes/exchange.py to use ExchangeService.get_available_slots()
- Remove all business logic from get_available_slots endpoint
- Add AvailabilityRepository to ExchangeService dependencies
- Add Availability and BookableSlot imports to ExchangeService
- Fix import path for validate_date_in_range (use date_validation module)
- Remove unused user_repo variable and import from routes/invites.py
- Fix mypy error in ValidationError by adding proper type annotation

backend/routes/profile.py

@@ -1,41 +1,25 @@
 """Profile routes for user contact details."""
 
-from fastapi import APIRouter, Depends, HTTPException
-from sqlalchemy import select
+from fastapi import APIRouter, Depends
 from sqlalchemy.ext.asyncio import AsyncSession
 
 from auth import require_permission
 from database import get_db
 from models import Permission, User
 from schemas import ProfileResponse, ProfileUpdate
-from validation import validate_profile_fields
+from services.profile import ProfileService
 
 router = APIRouter(prefix="/api/profile", tags=["profile"])
 
 
-async def get_godfather_email(db: AsyncSession, godfather_id: int | None) -> str | None:
-    """Get the email of a godfather user by ID."""
-    if not godfather_id:
-        return None
-    result = await db.execute(select(User.email).where(User.id == godfather_id))
-    return result.scalar_one_or_none()
-
-
 @router.get("", response_model=ProfileResponse)
 async def get_profile(
     current_user: User = Depends(require_permission(Permission.MANAGE_OWN_PROFILE)),
     db: AsyncSession = Depends(get_db),
 ) -> ProfileResponse:
     """Get the current user's profile (contact details and godfather)."""
-    godfather_email = await get_godfather_email(db, current_user.godfather_id)
-
-    return ProfileResponse(
-        contact_email=current_user.contact_email,
-        telegram=current_user.telegram,
-        signal=current_user.signal,
-        nostr_npub=current_user.nostr_npub,
-        godfather_email=godfather_email,
-    )
+    service = ProfileService(db)
+    return await service.get_profile(current_user)
 
 
 @router.put("", response_model=ProfileResponse)
@@ -45,36 +29,5 @@ async def update_profile(
     current_user: User = Depends(require_permission(Permission.MANAGE_OWN_PROFILE)),
 ) -> ProfileResponse:
     """Update the current user's profile (contact details)."""
-    # Validate all fields
-    errors = validate_profile_fields(
-        contact_email=data.contact_email,
-        telegram=data.telegram,
-        signal=data.signal,
-        nostr_npub=data.nostr_npub,
-    )
-
-    if errors:
-        # Keep field_errors format for backward compatibility with frontend
-        raise HTTPException(
-            status_code=422,
-            detail={"field_errors": errors},
-        )
-
-    # Update fields
-    current_user.contact_email = data.contact_email
-    current_user.telegram = data.telegram
-    current_user.signal = data.signal
-    current_user.nostr_npub = data.nostr_npub
-
-    await db.commit()
-    await db.refresh(current_user)
-
-    godfather_email = await get_godfather_email(db, current_user.godfather_id)
-
-    return ProfileResponse(
-        contact_email=current_user.contact_email,
-        telegram=current_user.telegram,
-        signal=current_user.signal,
-        nostr_npub=current_user.nostr_npub,
-        godfather_email=godfather_email,
-    )
+    service = ProfileService(db)
+    return await service.update_profile(current_user, data)