Update admin theme/layout and refresh README details.

Align the project baseline with the latest admin interface styling and layout structure while documenting setup and usage updates in README.

apps/api/tests/db/test_token_cleanup.py

@@ -0,0 +1,44 @@
+from __future__ import annotations
+
+from datetime import UTC, datetime, timedelta
+
+from app.core.database import session_scope
+from app.db.token_cleanup import cleanup_expired_tokens
+from app.modules.auth.models import EmailVerificationToken, PasswordResetToken, RefreshToken
+from app.modules.users.repository import get_user_by_email
+
+
+def test_cleanup_expired_tokens_removes_stale_rows():
+    user = get_user_by_email("admin@compton.example")
+    now = datetime.now(UTC)
+    with session_scope() as db:
+        db.add(
+            RefreshToken(
+                user_id=user.id,
+                token_hash="f" * 64,
+                family_id="fam-cleanup-1",
+                expires_at=now - timedelta(days=2),
+                revoked_at=now - timedelta(days=2),
+            )
+        )
+        db.add(
+            PasswordResetToken(
+                user_id=user.id,
+                token_hash="e" * 64,
+                expires_at=now - timedelta(days=1),
+                used_at=None,
+            )
+        )
+        db.add(
+            EmailVerificationToken(
+                user_id=user.id,
+                token_hash="d" * 64,
+                expires_at=now - timedelta(days=1),
+                used_at=None,
+            )
+        )
+
+    result = cleanup_expired_tokens(retention_days=1)
+    assert result["refresh_tokens_deleted"] >= 1
+    assert result["password_reset_tokens_deleted"] >= 1
+    assert result["email_verification_tokens_deleted"] >= 1