feat(pinia-orm): Change orderBy execution

[CodeDredd]

🔗 Linked issue

closes #1461

❓ Type of change

• [x] 📖 Documentation (updates to the documentation or readme)
• [ ] 🐞 Bug fix (a non-breaking change that fixes an issue)
• [x] 👌 Enhancement (improving an existing functionality like performance)
• [ ] ✨ New feature (a non-breaking change that adds functionality)
• [ ] ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

This PR makes some improvements to orderBy.

• orderBy is now excuted after relation ship loading so you can access nested data
• orderBy support now dot notation role.name

• it's now also possible to order by pivot data with some small help of useSotrBy

  
  class User extends Model {
    static entity = 'users'
  
    @Attr() id!: number
    @Str('') name!: string
    @BelongsToMany(() => Role, () => RoleUser, 'user_id', 'role_id')
    roles!: Role[]
  }
  
  class Role extends Model {
    static entity = 'roles'
  
    @Attr() id!: number
    @BelongsToMany(() => User, () => RoleUser, 'role_id', 'user_id')
    users!: User[]
  
    pivot!: RoleUser
  }
  
  class RoleUser extends Model {
    static entity = 'roleUser'
  
    static primaryKey = ['role_id', 'user_id']
  
    @Attr() role_id!: number
    @Attr() user_id!: number
    @Attr() level!: number
  }

const users = userRepo.with('roles').orderBy((user) => { user.roles = useSortBy(user.roles, [['pivot.level', 'asc']]) }).get()

// this returns

users = [ { id: 1, name: 'James', roles: [ { id: 2, users: [], pivot_roleUser: null, pivot: ... }, { id: 1, users: [], pivot_roleUser: null, pivot: ... }, ], }, { id: 2, name: 'Andy', roles: [ { id: 1, users: [], pivot_roleUser: null, pivot: ... }, ], }, { id: 3, name: 'David', roles: [] }, ]

### 📝 Checklist

<!-- Put an `x` in all the boxes that apply. -->
<!-- If your change requires a documentation PR, please link it appropriately -->
<!-- If you're unsure about any of these, don't hesitate to ask. We're here to help! -->

- [ ] I have linked an issue or discussion.
- [ ] I have updated the documentation accordingly.