Initial project scaffold: FastAPI backend + Svelte 5 frontend

Backend (uv): FastAPI app with routers (foods, log, targets, OFF proxy),
SQLAlchemy models, Pydantic schemas, migration runner + 0001 initial schema,
example pytest suite (7 tests).
Frontend (npm): Vite 7 + Svelte 5 runes, lib/ (api, stores, scanner, format)
per spec §7, placeholder components, example vitest suite (4 tests).
SPEC.md §1: registered uvicorn and Vitest (rule §8.3.3).

backend/models.py

@@ -0,0 +1,80 @@
+"""SQLAlchemy ORM models (SPEC.md §2). Separate from Pydantic schemas (spec §1)."""
+
+from datetime import date, datetime
+
+from sqlalchemy import CheckConstraint, ForeignKey
+from sqlalchemy.orm import Mapped, mapped_column, relationship
+
+from database import Base
+
+
+class Food(Base):
+    __tablename__ = "foods"
+    __table_args__ = (
+        # Meal nutrition is derived from components, never stored (spec §2.1)
+        CheckConstraint("is_meal = 1 OR calories_per_unit IS NOT NULL"),
+    )
+
+    id: Mapped[int] = mapped_column(primary_key=True)
+    name: Mapped[str]
+    brand: Mapped[str | None]
+    barcode: Mapped[str | None] = mapped_column(unique=True)
+    source: Mapped[str]  # "openfoodfacts" | "manual" | "meal"
+    is_meal: Mapped[bool] = mapped_column(default=False)
+    unit_type: Mapped[str] = mapped_column(default="weight")  # "weight" | "count"
+    calories_per_unit: Mapped[float | None]
+    protein_per_unit: Mapped[float | None]
+    carbs_per_unit: Mapped[float | None]
+    fat_per_unit: Mapped[float | None]
+    fiber_per_unit: Mapped[float | None]
+    saturated_fat_per_unit: Mapped[float | None]
+    sugars_per_unit: Mapped[float | None]
+    sodium_per_unit: Mapped[float | None]
+    serving_size_g: Mapped[float | None]
+    serving_name: Mapped[str | None]
+    off_data: Mapped[str | None]  # raw OFF JSON blob as TEXT
+    deleted_at: Mapped[datetime | None]
+    created_at: Mapped[datetime]
+    updated_at: Mapped[datetime]
+
+    components: Mapped[list["MealComponent"]] = relationship(
+        foreign_keys="MealComponent.meal_id", back_populates="meal"
+    )
+
+
+class MealComponent(Base):
+    __tablename__ = "meal_components"
+
+    id: Mapped[int] = mapped_column(primary_key=True)
+    meal_id: Mapped[int] = mapped_column(ForeignKey("foods.id"))
+    food_id: Mapped[int] = mapped_column(ForeignKey("foods.id"))
+    quantity: Mapped[float]
+
+    meal: Mapped[Food] = relationship(foreign_keys=[meal_id], back_populates="components")
+    food: Mapped[Food] = relationship(foreign_keys=[food_id])
+
+
+class DailyLogEntry(Base):
+    __tablename__ = "daily_log"
+
+    id: Mapped[int] = mapped_column(primary_key=True)
+    date: Mapped[date]
+    food_id: Mapped[int] = mapped_column(ForeignKey("foods.id"))
+    quantity: Mapped[float]
+    meal_slot: Mapped[str | None]  # "breakfast" | "lunch" | "dinner" | "snack"
+    sort_order: Mapped[int] = mapped_column(default=0)
+    created_at: Mapped[datetime]
+
+    food: Mapped[Food] = relationship()
+
+
+class Target(Base):
+    __tablename__ = "targets"
+
+    id: Mapped[int] = mapped_column(primary_key=True)
+    start_date: Mapped[date]
+    end_date: Mapped[date | None]  # null = currently active
+    calories: Mapped[int]
+    protein_g: Mapped[float | None]
+    carbs_g: Mapped[float | None]
+    fat_g: Mapped[float | None]