feat: add Phase 4 Logging & Tracking — inline set logging, history views

Add workout logging so users can track sets, reps, weight, and a
"felt easy?" toggle inline from the workout day view via HTMX.
Sessions auto-create on first log. History page shows past sessions
with detailed per-exercise breakdowns.

New services: WorkoutSessionService, LogService
New routes: POST /log, /log/{id}/edit, /log/{id}/delete, GET /history, /history/{id}
New templates: log_form, log_entry, session_card, log_history, session_detail
Modified: exercise_card (inline logging), nav (History link), workouts route (session context)

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

tests/test_log_service.py

@@ -0,0 +1,107 @@
+"""Tests for the LogService class."""
+
+from datetime import date
+
+from sqlmodel import SQLModel, Session, create_engine
+
+from app.models.user import User
+from app.models.exercise import Exercise
+from app.models.workout_day import WorkoutDay
+from app.models.workout_session import WorkoutSession
+from app.models.workout_log import WorkoutLog
+from app.services.log_service import LogService
+
+
+class TestLogService:
+    """Tests for workout log CRUD operations."""
+
+    def _setup(self):
+        """Create an in-memory DB with prerequisite data."""
+        engine = create_engine("sqlite:///:memory:")
+        SQLModel.metadata.create_all(engine)
+        session = Session(engine)
+
+        user = User(username="phil", password_hash="h", display_name="Phillip")
+        day = WorkoutDay(name="Push", day_number=1, description="Push day")
+        exercise = Exercise(
+            name="DB Chest Press", muscle_group="Chest",
+            workout_day="Push", sets=3, tempo="3-1-2", form_cues="...",
+        )
+        session.add_all([user, day, exercise])
+        session.commit()
+        session.refresh(user)
+        session.refresh(day)
+        session.refresh(exercise)
+
+        ws = WorkoutSession(
+            user_id=user.id, workout_day_id=day.id, date=date.today(),
+        )
+        session.add(ws)
+        session.commit()
+        session.refresh(ws)
+
+        service = LogService(session)
+        return session, service, ws, exercise
+
+    def test_create_log_entry(self) -> None:
+        """create_log should insert a new log entry."""
+        session, service, ws, exercise = self._setup()
+        log = service.create_log(
+            session_id=ws.id,
+            exercise_id=exercise.id,
+            set_number=1,
+            reps_completed=8,
+            weight_used="30 lbs",
+            felt_easy=False,
+        )
+        assert log.id is not None
+        assert log.reps_completed == 8
+        session.close()
+
+    def test_list_logs_for_session(self) -> None:
+        """list_logs_for_session should return all logs for a session."""
+        session, service, ws, exercise = self._setup()
+        service.create_log(ws.id, exercise.id, 1, 8, "30 lbs", False)
+        service.create_log(ws.id, exercise.id, 2, 8, "30 lbs", False)
+        service.create_log(ws.id, exercise.id, 3, 7, "30 lbs", True)
+        logs = service.list_logs_for_session(ws.id)
+        assert len(logs) == 3
+        session.close()
+
+    def test_list_logs_for_exercise_in_session(self) -> None:
+        """list_logs_for_exercise should filter by exercise within a session."""
+        session, service, ws, exercise = self._setup()
+        service.create_log(ws.id, exercise.id, 1, 8, "30 lbs", False)
+        logs = service.list_logs_for_exercise(ws.id, exercise.id)
+        assert len(logs) == 1
+        session.close()
+
+    def test_update_log(self) -> None:
+        """update_log should modify an existing log entry."""
+        session, service, ws, exercise = self._setup()
+        log = service.create_log(ws.id, exercise.id, 1, 8, "30 lbs", False)
+        updated = service.update_log(log.id, reps_completed=10, felt_easy=True)
+        assert updated.reps_completed == 10
+        assert updated.felt_easy is True
+        session.close()
+
+    def test_delete_log(self) -> None:
+        """delete_log should remove a log entry."""
+        session, service, ws, exercise = self._setup()
+        log = service.create_log(ws.id, exercise.id, 1, 8, "30 lbs", False)
+        service.delete_log(log.id)
+        logs = service.list_logs_for_session(ws.id)
+        assert len(logs) == 0
+        session.close()
+
+    def test_get_latest_logs_for_exercise(self) -> None:
+        """get_latest_logs should return the most recent logs for an exercise."""
+        session, service, ws, exercise = self._setup()
+        service.create_log(ws.id, exercise.id, 1, 8, "30 lbs", False)
+        service.create_log(ws.id, exercise.id, 2, 8, "30 lbs", True)
+        logs = service.get_latest_logs_for_exercise(
+            user_id=ws.user_id,
+            exercise_id=exercise.id,
+        )
+        assert len(logs) >= 1
+        session.close()