Add Django site, Docker packaging, and beta/prod Gitea deploys.

Unignore site/ (was blocked by mkdocs /site rule), add compose/Docker/uv tooling, and split deploys so push to main goes to beta while prod stays manual.

site/core/tests.py

@@ -0,0 +1,29 @@
+from django.test import Client, TestCase, override_settings
+from django.urls import reverse
+
+
+class HealthzTests(TestCase):
+    def test_healthz_ok(self):
+        response = Client().get("/healthz/")
+        self.assertEqual(response.status_code, 200)
+        self.assertEqual(response.json()["status"], "ok")
+
+
+class UnderConstructionTests(TestCase):
+    @override_settings(SITE_UNDER_CONSTRUCTION=True)
+    def test_home_redirects_when_gated(self):
+        response = Client().get("/")
+        self.assertEqual(response.status_code, 302)
+        self.assertIn("/under-construction", response["Location"])
+
+    @override_settings(SITE_UNDER_CONSTRUCTION=False)
+    def test_home_ok_when_open(self):
+        response = Client().get("/")
+        self.assertEqual(response.status_code, 200)
+
+
+class PublicSmokeTests(TestCase):
+    def test_about_and_contact_get(self):
+        client = Client()
+        self.assertEqual(client.get(reverse("public:about")).status_code, 200)
+        self.assertEqual(client.get(reverse("public:contact")).status_code, 200)