feat: add initial database models and changelog for financial inputs and projects

models/project.py

@@ -0,0 +1,54 @@
+from __future__ import annotations
+
+from datetime import datetime
+from enum import Enum
+from typing import TYPE_CHECKING, List
+
+from sqlalchemy import DateTime, Enum as SQLEnum, Integer, String, Text
+from sqlalchemy.orm import Mapped, mapped_column, relationship
+from sqlalchemy.sql import func
+
+from config.database import Base
+
+if TYPE_CHECKING:  # pragma: no cover
+    from .scenario import Scenario
+
+
+class MiningOperationType(str, Enum):
+    """Supported mining operation categories."""
+
+    OPEN_PIT = "open_pit"
+    UNDERGROUND = "underground"
+    PLACER = "placer"
+    QUARRY = "quarry"
+    OTHER = "other"
+
+
+class Project(Base):
+    """Top-level mining project grouping multiple scenarios."""
+
+    __tablename__ = "projects"
+
+    id: Mapped[int] = mapped_column(Integer, primary_key=True, index=True)
+    name: Mapped[str] = mapped_column(String(255), nullable=False, unique=True)
+    location: Mapped[str | None] = mapped_column(String(255), nullable=True)
+    operation_type: Mapped[MiningOperationType] = mapped_column(
+        SQLEnum(MiningOperationType), nullable=False, default=MiningOperationType.OTHER
+    )
+    description: Mapped[str | None] = mapped_column(Text, nullable=True)
+    created_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), nullable=False, server_default=func.now()
+    )
+    updated_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), nullable=False, server_default=func.now(), onupdate=func.now()
+    )
+
+    scenarios: Mapped[List["Scenario"]] = relationship(
+        "Scenario",
+        back_populates="project",
+        cascade="all, delete-orphan",
+        passive_deletes=True,
+    )
+
+    def __repr__(self) -> str:  # pragma: no cover - helpful for debugging
+        return f"Project(id={self.id!r}, name={self.name!r})"