feat: define all 8 SQLModel tables

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

app/models/workout_log.py

@@ -0,0 +1,37 @@
+"""WorkoutLog model for per-exercise set logging.
+
+Each log entry records one set of one exercise within a session.
+"""
+
+from datetime import datetime
+from typing import Optional
+
+from sqlmodel import Field, SQLModel
+
+
+class WorkoutLog(SQLModel, table=True):
+    """A single set log for an exercise within a workout session.
+
+    Attributes:
+        id: Primary key, auto-incremented.
+        session_id: FK to workout_sessions table.
+        exercise_id: FK to exercises table.
+        set_number: Which set this is (1, 2, 3...).
+        reps_completed: Actual reps performed.
+        weight_used: Weight used as string (e.g., "30 lbs", "BW").
+        felt_easy: Whether the user felt the set was easy (progression signal).
+        notes: Optional notes about this specific set.
+        created_at: Timestamp when the record was created.
+    """
+
+    __tablename__ = "workout_logs"
+
+    id: Optional[int] = Field(default=None, primary_key=True)
+    session_id: int = Field(foreign_key="workout_sessions.id", index=True)
+    exercise_id: int = Field(foreign_key="exercises.id")
+    set_number: int = Field(default=1)
+    reps_completed: int = Field(default=0)
+    weight_used: str = Field(default="")
+    felt_easy: bool = Field(default=False)
+    notes: Optional[str] = Field(default=None)
+    created_at: datetime = Field(default_factory=datetime.utcnow)