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>

app/routes/history.py

@@ -0,0 +1,113 @@
+"""Log history routes for viewing past workout sessions.
+
+Displays a list of past sessions and detailed logs per session.
+"""
+
+import structlog
+from fastapi import APIRouter, Depends, Request
+from fastapi.responses import HTMLResponse
+from sqlmodel import Session
+
+from app.database import get_db_session
+from app.models.user import User
+from app.services.exercise_service import ExerciseService
+from app.services.log_service import LogService
+from app.services.workout_session_service import WorkoutSessionService
+from app.utils.auth import get_current_admin_user, get_active_profile_id
+
+logger = structlog.get_logger(__name__)
+
+router = APIRouter(prefix="/history", tags=["history"])
+
+
+@router.get("", response_class=HTMLResponse)
+async def log_history(
+    request: Request,
+    session: Session = Depends(get_db_session),
+    admin: User = Depends(get_current_admin_user),
+):
+    """Display log history for the active profile.
+
+    Shows a list of past workout sessions, most recent first.
+
+    Args:
+        request: The incoming HTTP request.
+        session: Database session.
+        admin: The authenticated admin user.
+
+    Returns:
+        Rendered log history page.
+    """
+    active_profile_id = get_active_profile_id(request)
+    active_profile = (
+        session.get(User, active_profile_id)
+        if active_profile_id
+        else None
+    )
+
+    sessions_list = []
+    if active_profile_id:
+        ws_service = WorkoutSessionService(session)
+        sessions_list = ws_service.list_sessions(user_id=active_profile_id)
+
+    # Resolve workout day names for display
+    exercise_service = ExerciseService(session)
+    days_by_id = {d.id: d for d in exercise_service.list_workout_days()}
+
+    templates = request.app.state.templates
+    return templates.TemplateResponse("pages/log_history.html", {
+        "request": request,
+        "sessions": sessions_list,
+        "days_by_id": days_by_id,
+        "active_profile": active_profile,
+        "admin": admin,
+    })
+
+
+@router.get("/{session_id}", response_class=HTMLResponse)
+async def session_detail(
+    session_id: int,
+    request: Request,
+    session: Session = Depends(get_db_session),
+    admin: User = Depends(get_current_admin_user),
+):
+    """Display detailed logs for a specific workout session.
+
+    Args:
+        session_id: The workout session ID.
+        request: The incoming HTTP request.
+        session: Database session.
+        admin: The authenticated admin user.
+
+    Returns:
+        Rendered session detail page.
+    """
+    ws_service = WorkoutSessionService(session)
+    ws = ws_service.get_session_by_id(session_id)
+
+    log_service = LogService(session)
+    logs = log_service.list_logs_for_session(session_id)
+
+    # Group logs by exercise
+    exercise_service = ExerciseService(session)
+    exercises_by_id = {}
+    logs_by_exercise = {}
+    for log in logs:
+        if log.exercise_id not in exercises_by_id:
+            exercises_by_id[log.exercise_id] = (
+                exercise_service.get_exercise_by_id(log.exercise_id)
+            )
+        logs_by_exercise.setdefault(log.exercise_id, []).append(log)
+
+    # Resolve workout day name
+    days_by_id = {d.id: d for d in exercise_service.list_workout_days()}
+
+    templates = request.app.state.templates
+    return templates.TemplateResponse("pages/session_detail.html", {
+        "request": request,
+        "workout_session": ws,
+        "logs_by_exercise": logs_by_exercise,
+        "exercises_by_id": exercises_by_id,
+        "days_by_id": days_by_id,
+        "admin": admin,
+    })