feat: add multi-tenant system with properties, organizations, and public booking

Implement complete multi-property architecture:
- Properties (groups of spaces) with public/private visibility
- Property managers (many-to-many) with role-based permissions
- Organizations with member management
- Anonymous/guest booking support via public API (/api/public/*)
- Property-scoped spaces, bookings, and settings
- Frontend: property selector, organization management, public booking views
- Migration script and updated seed data

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

backend/app/models/__init__.py

@@ -5,8 +5,19 @@ from app.models.booking import Booking
 from app.models.booking_template import BookingTemplate
 from app.models.google_calendar_token import GoogleCalendarToken
 from app.models.notification import Notification
+from app.models.organization import Organization
+from app.models.organization_member import OrganizationMember
+from app.models.property import Property
+from app.models.property_access import PropertyAccess
+from app.models.property_manager import PropertyManager
+from app.models.property_settings import PropertySettings
 from app.models.settings import Settings
 from app.models.space import Space
 from app.models.user import User
 
-__all__ = ["User", "Space", "Settings", "Booking", "BookingTemplate", "Notification", "AuditLog", "Attachment", "GoogleCalendarToken"]
+__all__ = [
+    "User", "Space", "Settings", "Booking", "BookingTemplate",
+    "Notification", "AuditLog", "Attachment", "GoogleCalendarToken",
+    "Property", "PropertyManager", "PropertyAccess", "PropertySettings",
+    "Organization", "OrganizationMember",
+]

backend/app/models/booking.py

@@ -1,7 +1,7 @@
 """Booking model."""
 from datetime import datetime
 
-from sqlalchemy import Column, DateTime, ForeignKey, Integer, String
+from sqlalchemy import Boolean, Column, DateTime, ForeignKey, Integer, String
 from sqlalchemy.orm import relationship
 
 from app.db.session import Base
@@ -13,8 +13,12 @@ class Booking(Base):
     __tablename__ = "bookings"
 
     id = Column(Integer, primary_key=True, index=True)
-    user_id = Column(Integer, ForeignKey("users.id"), nullable=False, index=True)
+    user_id = Column(Integer, ForeignKey("users.id"), nullable=True, index=True)
     space_id = Column(Integer, ForeignKey("spaces.id"), nullable=False, index=True)
+    guest_name = Column(String, nullable=True)
+    guest_email = Column(String, nullable=True)
+    guest_organization = Column(String, nullable=True)
+    is_anonymous = Column(Boolean, default=False, nullable=False)
     title = Column(String, nullable=False)
     description = Column(String, nullable=True)
     start_datetime = Column(DateTime, nullable=False, index=True)

backend/app/models/organization.py

@@ -0,0 +1,18 @@
+"""Organization model."""
+from datetime import datetime
+
+from sqlalchemy import Boolean, Column, DateTime, Integer, String
+
+from app.db.session import Base
+
+
+class Organization(Base):
+    """Organization model for grouping users."""
+
+    __tablename__ = "organizations"
+
+    id = Column(Integer, primary_key=True, index=True)
+    name = Column(String, nullable=False, unique=True, index=True)
+    description = Column(String, nullable=True)
+    is_active = Column(Boolean, default=True, nullable=False)
+    created_at = Column(DateTime, nullable=False, default=datetime.utcnow)

backend/app/models/organization_member.py

@@ -0,0 +1,17 @@
+"""OrganizationMember junction model."""
+from sqlalchemy import Column, ForeignKey, Integer, String, UniqueConstraint
+
+from app.db.session import Base
+
+
+class OrganizationMember(Base):
+    """Junction table linking organizations to their members."""
+
+    __tablename__ = "organization_members"
+
+    id = Column(Integer, primary_key=True, index=True)
+    organization_id = Column(Integer, ForeignKey("organizations.id"), nullable=False, index=True)
+    user_id = Column(Integer, ForeignKey("users.id"), nullable=False, index=True)
+    role = Column(String, nullable=False, default="member")  # "admin" or "member"
+
+    __table_args__ = (UniqueConstraint("organization_id", "user_id", name="uq_org_member"),)

backend/app/models/property.py

@@ -0,0 +1,20 @@
+"""Property model."""
+from datetime import datetime
+
+from sqlalchemy import Boolean, Column, DateTime, Integer, String
+
+from app.db.session import Base
+
+
+class Property(Base):
+    """Property model for multi-tenant property management."""
+
+    __tablename__ = "properties"
+
+    id = Column(Integer, primary_key=True, index=True)
+    name = Column(String, nullable=False, index=True)
+    description = Column(String, nullable=True)
+    address = Column(String, nullable=True)
+    is_public = Column(Boolean, default=True, nullable=False)
+    is_active = Column(Boolean, default=True, nullable=False)
+    created_at = Column(DateTime, nullable=False, default=datetime.utcnow)

backend/app/models/property_access.py

@@ -0,0 +1,19 @@
+"""PropertyAccess model."""
+from datetime import datetime
+
+from sqlalchemy import Column, DateTime, ForeignKey, Integer
+
+from app.db.session import Base
+
+
+class PropertyAccess(Base):
+    """Tracks which users/organizations have access to private properties."""
+
+    __tablename__ = "property_access"
+
+    id = Column(Integer, primary_key=True, index=True)
+    property_id = Column(Integer, ForeignKey("properties.id"), nullable=False, index=True)
+    user_id = Column(Integer, ForeignKey("users.id"), nullable=True, index=True)
+    organization_id = Column(Integer, ForeignKey("organizations.id"), nullable=True, index=True)
+    granted_by = Column(Integer, ForeignKey("users.id"), nullable=True)
+    created_at = Column(DateTime, nullable=False, default=datetime.utcnow)

backend/app/models/property_manager.py

@@ -0,0 +1,16 @@
+"""PropertyManager junction model."""
+from sqlalchemy import Column, ForeignKey, Integer, UniqueConstraint
+
+from app.db.session import Base
+
+
+class PropertyManager(Base):
+    """Junction table linking properties to their managers."""
+
+    __tablename__ = "property_managers"
+
+    id = Column(Integer, primary_key=True, index=True)
+    property_id = Column(Integer, ForeignKey("properties.id"), nullable=False, index=True)
+    user_id = Column(Integer, ForeignKey("users.id"), nullable=False, index=True)
+
+    __table_args__ = (UniqueConstraint("property_id", "user_id", name="uq_property_manager"),)

backend/app/models/property_settings.py

@@ -0,0 +1,20 @@
+"""PropertySettings model."""
+from sqlalchemy import Boolean, Column, ForeignKey, Integer
+
+from app.db.session import Base
+
+
+class PropertySettings(Base):
+    """Per-property scheduling settings."""
+
+    __tablename__ = "property_settings"
+
+    id = Column(Integer, primary_key=True, index=True)
+    property_id = Column(Integer, ForeignKey("properties.id"), nullable=False, unique=True, index=True)
+    working_hours_start = Column(Integer, nullable=True)
+    working_hours_end = Column(Integer, nullable=True)
+    min_duration_minutes = Column(Integer, nullable=True)
+    max_duration_minutes = Column(Integer, nullable=True)
+    max_bookings_per_day_per_user = Column(Integer, nullable=True)
+    require_approval = Column(Boolean, default=True, nullable=False)
+    min_hours_before_cancel = Column(Integer, nullable=True)

backend/app/models/space.py

@@ -1,5 +1,6 @@
 """Space model."""
-from sqlalchemy import Boolean, Column, Integer, String
+from sqlalchemy import Boolean, Column, ForeignKey, Integer, String
+from sqlalchemy.orm import relationship
 
 from app.db.session import Base
 
@@ -15,9 +16,12 @@ class Space(Base):
     capacity = Column(Integer, nullable=False)
     description = Column(String, nullable=True)
     is_active = Column(Boolean, default=True, nullable=False)
+    property_id = Column(Integer, ForeignKey("properties.id"), nullable=True, index=True)
 
     # Per-space scheduling settings (NULL = use global default)
     working_hours_start = Column(Integer, nullable=True)
     working_hours_end = Column(Integer, nullable=True)
     min_duration_minutes = Column(Integer, nullable=True)
     max_duration_minutes = Column(Integer, nullable=True)
+
+    property = relationship("Property", backref="spaces")

backend/app/models/user.py

@@ -14,7 +14,7 @@ class User(Base):
     email = Column(String, unique=True, index=True, nullable=False)
     full_name = Column(String, nullable=False)
     hashed_password = Column(String, nullable=False)
-    role = Column(String, nullable=False, default="user")  # "admin" or "user"
+    role = Column(String, nullable=False, default="user")  # "superadmin"/"manager"/"user"
     organization = Column(String, nullable=True)
     is_active = Column(Boolean, default=True, nullable=False)
     timezone = Column(String(50), default="UTC", nullable=False)  # IANA timezone
@@ -26,3 +26,5 @@ class User(Base):
     google_calendar_token = relationship(
         "GoogleCalendarToken", back_populates="user", uselist=False
     )
+    managed_properties = relationship("PropertyManager", backref="user", cascade="all, delete-orphan")
+    organization_memberships = relationship("OrganizationMember", backref="user", cascade="all, delete-orphan")