feat(crm,ops): proceso comercial (solicitudes/RFQ, tarifas, cotizaciones) + Operaciones (embarques)

Diagrama 1 (CRM comercial) y Diagrama 2 (Operaciones) del spec de agente de carga:
- crm.service_requests (RFQ) + crm.rate_requests (solicitud de tarifas a proveedores)
- crm.quotes + crm.quote_items: conceptos costo/venta/margen, totales automáticos,
  estados borrador→enviada→aceptada/rechazada
- schema ops: ops.shipments (booking, Cut Off, ETD/ETA, naviera/agente aduanal/destino)
  y ops.shipment_documents (MBL/HBL, MAWB/HAWB, CMR…)
- liberar-a-operaciones: crea el embarque desde la cotización aceptada
- migración b3c4d5e6f7a8, routers/permisos, seed del flujo completo
- 52 tests pytest en verde

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

backend/api/v1/modules/crm/quotes/models.py

@@ -0,0 +1,60 @@
+from datetime import date, datetime
+
+from sqlalchemy import Date, DateTime, ForeignKey, Integer, Numeric, String, Text, text
+from sqlalchemy.orm import Mapped, mapped_column
+
+from api.v1.common.base_models import TenantScopedMixin, TimestampMixin
+from core.database import Base
+
+
+class Quote(Base, TenantScopedMixin, TimestampMixin):
+    """Cotización (Diagrama 1, pasos 7-9). Integra los conceptos de costo/venta."""
+
+    __tablename__ = "quotes"
+    __table_args__ = {"schema": "crm"}
+
+    id: Mapped[int] = mapped_column(Integer, primary_key=True, index=True)
+    reference: Mapped[str | None] = mapped_column(String(40), nullable=True, index=True)
+    service_request_id: Mapped[int | None] = mapped_column(
+        Integer, ForeignKey("crm.service_requests.id"), nullable=True, index=True
+    )
+    account_id: Mapped[int | None] = mapped_column(
+        Integer, ForeignKey("crm.accounts.id"), nullable=True, index=True
+    )
+    currency: Mapped[str] = mapped_column(String(3), nullable=False, server_default=text("'USD'"))
+    # borrador | enviada | aceptada | rechazada
+    status: Mapped[str] = mapped_column(String(20), nullable=False, server_default=text("'borrador'"), index=True)
+    issue_date: Mapped[date | None] = mapped_column(Date, nullable=True)
+    valid_until: Mapped[date | None] = mapped_column(Date, nullable=True)
+    total_cost: Mapped[float] = mapped_column(Numeric(14, 2), nullable=False, server_default=text("0"))
+    total_sale: Mapped[float] = mapped_column(Numeric(14, 2), nullable=False, server_default=text("0"))
+    sent_at: Mapped[datetime | None] = mapped_column(DateTime, nullable=True)
+    accepted_at: Mapped[datetime | None] = mapped_column(DateTime, nullable=True)
+    rejected_at: Mapped[datetime | None] = mapped_column(DateTime, nullable=True)
+    notes: Mapped[str | None] = mapped_column(Text, nullable=True)
+    terms: Mapped[str | None] = mapped_column(Text, nullable=True)
+    owner_user_id: Mapped[str | None] = mapped_column(String(64), nullable=True, index=True)
+    created_by: Mapped[str | None] = mapped_column(String(64), nullable=True)
+    updated_by: Mapped[str | None] = mapped_column(String(64), nullable=True)
+
+
+class QuoteItem(Base, TenantScopedMixin, TimestampMixin):
+    """Concepto de una cotización (flete, transporte terrestre, despacho, gastos destino, otros)."""
+
+    __tablename__ = "quote_items"
+    __table_args__ = {"schema": "crm"}
+
+    id: Mapped[int] = mapped_column(Integer, primary_key=True, index=True)
+    quote_id: Mapped[int] = mapped_column(
+        Integer, ForeignKey("crm.quotes.id"), nullable=False, index=True
+    )
+    # flete_internacional | transporte_terrestre | despacho_aduanal | gastos_destino | otros
+    concept: Mapped[str] = mapped_column(String(60), nullable=False)
+    description: Mapped[str | None] = mapped_column(String(255), nullable=True)
+    supplier_id: Mapped[int | None] = mapped_column(
+        Integer, ForeignKey("crm.suppliers.id"), nullable=True
+    )
+    quantity: Mapped[float] = mapped_column(Numeric(12, 2), nullable=False, server_default=text("1"))
+    unit_cost: Mapped[float] = mapped_column(Numeric(14, 2), nullable=False, server_default=text("0"))
+    unit_sale: Mapped[float] = mapped_column(Numeric(14, 2), nullable=False, server_default=text("0"))
+    currency: Mapped[str | None] = mapped_column(String(3), nullable=True)