feat: define all 8 SQLModel tables

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

app/models/user_exercise_program.py

@@ -0,0 +1,37 @@
+"""UserExerciseProgram model for per-user exercise programming.
+
+Links a user to an exercise with week 1 and week 4 rep/weight targets.
+"""
+
+from datetime import datetime
+from typing import Optional
+
+from sqlmodel import Field, SQLModel
+
+
+class UserExerciseProgram(SQLModel, table=True):
+    """Per-user programming for a specific exercise.
+
+    Attributes:
+        id: Primary key, auto-incremented.
+        user_id: FK to users table.
+        exercise_id: FK to exercises table.
+        wk1_reps: Week 1 target reps (string to support "30 sec" style).
+        wk4_reps: Week 4 target reps.
+        wk1_weight: Week 1 target weight (e.g., "30 lbs", "BW").
+        wk4_weight: Week 4 target weight.
+        created_at: Timestamp when the record was created.
+        updated_at: Timestamp of the last update.
+    """
+
+    __tablename__ = "user_exercise_programs"
+
+    id: Optional[int] = Field(default=None, primary_key=True)
+    user_id: int = Field(foreign_key="users.id", index=True)
+    exercise_id: int = Field(foreign_key="exercises.id", index=True)
+    wk1_reps: str = Field(default="")
+    wk4_reps: str = Field(default="")
+    wk1_weight: str = Field(default="")
+    wk4_weight: str = Field(default="")
+    created_at: datetime = Field(default_factory=datetime.utcnow)
+    updated_at: datetime = Field(default_factory=datetime.utcnow)