Initial public commit

Daybook: a self-hosted, multi-user Django + DRF app where agents, scripts,
or people publish artifacts and each logged-in user browses their own
time-ordered, label-filterable feed.

This squashes prior local development history (kept privately on a separate
branch) into a single clean starting point for the public repository.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

templates/artifacts/settings_demo_data.html

@@ -0,0 +1,10 @@
+{% extends "artifacts/settings_base.html" %}
+
+{% block settings_content %}
+  <h2>Demo Data</h2>
+  <p>Generate one sample artifact of every supported kind (markdown, HTML fragment, full HTML, deck, image, PDF, binary), tagged "demo" and dated today.</p>
+  <form method="post">
+    {% csrf_token %}
+    <button type="submit">Generate Demo Data</button>
+  </form>
+{% endblock %}