feat(crm): dominio backend (cuentas, contactos, prospectos, embudos, oportunidades, actividades)

- Nuevo schema `crm` con 7 tablas multi-tenant (TenantScopedMixin + soft delete)
- Módulos FastAPI por dominio: models/dto/service/routes (patrón example)
- Métricas del dashboard (KPIs + embudo por etapa)
- Conversión de prospecto → cuenta/contacto/oportunidad (idempotente)
- Movimiento de oportunidad entre etapas (Kanban) con estado/probabilidad derivados
- 25 permisos registrados en PermissionRegistry
- Migración Alembic con upgrade/downgrade completos
- 24 tests de servicios (pytest) en verde

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

backend/api/v1/modules/crm/pipelines/dto.py

@@ -0,0 +1,58 @@
+from datetime import datetime
+
+from pydantic import BaseModel, ConfigDict, Field
+
+
+class PipelineCreate(BaseModel):
+    name: str = Field(..., min_length=1, max_length=120)
+    is_default: bool = False
+
+
+class PipelineUpdate(BaseModel):
+    name: str | None = Field(None, min_length=1, max_length=120)
+    is_default: bool | None = None
+
+
+class PipelineResponse(BaseModel):
+    model_config = ConfigDict(from_attributes=True)
+
+    id: int
+    name: str
+    is_default: bool
+    tenant_id: int
+    company_id: int
+    created_at: datetime
+    updated_at: datetime
+
+
+class StageCreate(BaseModel):
+    pipeline_id: int
+    name: str = Field(..., min_length=1, max_length=120)
+    position: int = Field(0, ge=0)
+    probability: int = Field(0, ge=0, le=100)
+    is_won: bool = False
+    is_lost: bool = False
+
+
+class StageUpdate(BaseModel):
+    name: str | None = Field(None, min_length=1, max_length=120)
+    position: int | None = Field(None, ge=0)
+    probability: int | None = Field(None, ge=0, le=100)
+    is_won: bool | None = None
+    is_lost: bool | None = None
+
+
+class StageResponse(BaseModel):
+    model_config = ConfigDict(from_attributes=True)
+
+    id: int
+    pipeline_id: int
+    name: str
+    position: int
+    probability: int
+    is_won: bool
+    is_lost: bool
+    tenant_id: int
+    company_id: int
+    created_at: datetime
+    updated_at: datetime