feat(src): add productivity API endpoint

- **New Features**:
  - Added new URL route for productivity API at `/productivity/`
  - Integrated `src.api.productivity.urls` module into the main URL configuration
```

src/api/productivity/urls.py

@@ -0,0 +1,46 @@
+from django.urls import path
+
+from . import views
+
+urlpatterns = [
+    path("", views.productivity_dashboard, name="productivity_dashboard"),
+    # Notes
+    path("notes/", views.note_list, name="note_list"),
+    path("notes/create/", views.note_create, name="note_create"),
+    path("notes/<int:pk>/edit/", views.note_edit, name="note_edit"),
+    path("notes/<int:pk>/delete/", views.note_delete, name="note_delete"),
+    # Time entries
+    path("time-entries/", views.timeentry_list, name="timeentry_list"),
+    path("time-entries/create/", views.timeentry_create, name="timeentry_create"),
+    path("time-entries/<int:pk>/edit/", views.timeentry_edit, name="timeentry_edit"),
+    path(
+        "time-entries/<int:pk>/delete/",
+        views.timeentry_delete,
+        name="timeentry_delete",
+    ),
+]
+
+from django.urls import path
+
+from . import views
+
+urlpatterns = [
+    # Dashboard
+    path("", views.productivity_dashboard, name="productivity_dashboard"),
+    # Notes
+    path("notes/", views.note_list, name="note_list"),
+    path("notes/create/", views.note_create, name="note_create"),
+    path("notes/<int:pk>/edit/", views.note_edit, name="note_edit"),
+    path("notes/<int:pk>/delete/", views.note_delete, name="note_delete"),
+    # Time entries
+    path("time-entries/", views.timeentry_list, name="timeentry_list"),
+    path("time-entries/create/", views.timeentry_create, name="timeentry_create"),
+    path("time-entries/<int:pk>/edit/", views.timeentry_edit, name="timeentry_edit"),
+    path(
+        "time-entries/<int:pk>/delete/",
+        views.timeentry_delete,
+        name="timeentry_delete",
+    ),
+]
+
+

src/api/productivity/views.py

@@ -0,0 +1,166 @@
+from datetime import datetime
+
+from django.shortcuts import get_object_or_404, redirect, render
+from django.views.decorators.http import require_http_methods
+
+from src.models.productivity import Note, TimeEntry
+from src.models.projects import Project, Task
+
+
+def productivity_dashboard(request):
+    recent_notes = Note.objects.all()[:5]
+    recent_time_entries = (
+        TimeEntry.objects.select_related("project", "task").all()[:5]
+    )
+    total_tracked_hours = (
+        sum(
+            (entry.duration.total_seconds() for entry in recent_time_entries if entry.duration),
+            0,
+        )
+        / 3600
+        if recent_time_entries
+        else 0
+    )
+    return render(
+        request,
+        "productivity/dashboard.html",
+        {
+            "recent_notes": recent_notes,
+            "recent_time_entries": recent_time_entries,
+            "total_tracked_hours": total_tracked_hours,
+        },
+    )
+
+
+def note_list(request):
+    notes = Note.objects.all()
+    return render(request, "productivity/note_list.html", {"notes": notes})
+
+
+def note_create(request):
+    if request.method == "POST":
+        title = request.POST.get("title", "").strip()
+        content = request.POST.get("content", "").strip()
+
+        if title and content:
+            Note.objects.create(title=title, content=content)
+            return redirect("note_list")
+
+    return render(request, "productivity/note_form.html")
+
+
+def note_edit(request, pk):
+    note = get_object_or_404(Note, pk=pk)
+
+    if request.method == "POST":
+        title = request.POST.get("title", "").strip()
+        content = request.POST.get("content", "").strip()
+
+        if title and content:
+            note.title = title
+            note.content = content
+            note.save()
+            return redirect("note_list")
+
+    return render(request, "productivity/note_form.html", {"note": note})
+
+
+@require_http_methods(["DELETE", "POST"])
+def note_delete(request, pk):
+    note = get_object_or_404(Note, pk=pk)
+    note.delete()
+    return redirect("note_list")
+
+
+def _parse_datetime(value: str):
+    if not value:
+        return None
+    # Expect HTML datetime-local format: "YYYY-MM-DDTHH:MM"
+    try:
+        return datetime.fromisoformat(value)
+    except ValueError:
+        return None
+
+
+def timeentry_list(request):
+    time_entries = TimeEntry.objects.select_related("project", "task").all()
+    return render(
+        request,
+        "productivity/timeentry_list.html",
+        {"time_entries": time_entries},
+    )
+
+
+def timeentry_create(request):
+    projects = Project.objects.all()
+    tasks = Task.objects.all()
+
+    if request.method == "POST":
+        project_id = request.POST.get("project")
+        task_id = request.POST.get("task")
+        description = request.POST.get("description", "").strip()
+        start_time_raw = request.POST.get("start_time", "").strip()
+        end_time_raw = request.POST.get("end_time", "").strip()
+
+        start_time = _parse_datetime(start_time_raw)
+        end_time = _parse_datetime(end_time_raw)
+
+        if description and start_time:
+            project = Project.objects.filter(id=project_id).first() if project_id else None
+            task = Task.objects.filter(id=task_id).first() if task_id else None
+
+            TimeEntry.objects.create(
+                project=project,
+                task=task,
+                description=description,
+                start_time=start_time,
+                end_time=end_time,
+            )
+            return redirect("timeentry_list")
+
+    return render(
+        request,
+        "productivity/timeentry_form.html",
+        {"projects": projects, "tasks": tasks},
+    )
+
+
+def timeentry_edit(request, pk):
+    time_entry = get_object_or_404(TimeEntry, pk=pk)
+    projects = Project.objects.all()
+    tasks = Task.objects.all()
+
+    if request.method == "POST":
+        project_id = request.POST.get("project")
+        task_id = request.POST.get("task")
+        description = request.POST.get("description", "").strip()
+        start_time_raw = request.POST.get("start_time", "").strip()
+        end_time_raw = request.POST.get("end_time", "").strip()
+
+        start_time = _parse_datetime(start_time_raw)
+        end_time = _parse_datetime(end_time_raw)
+
+        if description and start_time:
+            time_entry.project = Project.objects.filter(id=project_id).first() if project_id else None
+            time_entry.task = Task.objects.filter(id=task_id).first() if task_id else None
+            time_entry.description = description
+            time_entry.start_time = start_time
+            time_entry.end_time = end_time
+            time_entry.save()
+            return redirect("timeentry_list")
+
+    context = {
+        "time_entry": time_entry,
+        "projects": projects,
+        "tasks": tasks,
+    }
+    return render(request, "productivity/timeentry_form.html", context)
+
+
+@require_http_methods(["DELETE", "POST"])
+def timeentry_delete(request, pk):
+    time_entry = get_object_or_404(TimeEntry, pk=pk)
+    time_entry.delete()
+    return redirect("timeentry_list")
+
+

src/urls.py

@@ -11,4 +11,5 @@ urlpatterns = [
     path("clients/", include("src.api.clients.urls")),
     path("projects/", include("src.api.projects.urls")),
     path("finance/", include("src.api.finance.urls")),
+    path("productivity/", include("src.api.productivity.urls")),
 ]