Fix infinite re-fetch loop in useJailConfigs

The hook was passing an inline onSuccess callback to useListData, which
included onSuccess in its internal refresh function's dependency array.
This caused refresh to be recreated on each render, which triggered the
useEffect, which fired the fetch, which completed and caused a re-render,
creating an infinite loop.

Wrap onSuccess in useCallback with empty dependencies so it maintains a
stable reference across renders. This allows refresh to be stable when
its dependencies don't change, breaking the cycle.

Add documentation to Refactoring.md explaining the onSuccess stability
requirement for useListData callers.

Also add tests for useJailConfigs to verify it doesn't trigger infinite
refetches with stable onSuccess callback.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Docs/Refactoring.md

@@ -16,4 +16,5 @@ This document catalogues architecture violations, code smells, and structural is
 - Moved config file exceptions (`ConfigDirError`, `ConfigFileNotFoundError`, `ConfigFileExistsError`, `ConfigFileWriteError`, `ConfigFileNameError`) from `backend/app/services/raw_config_io_service.py` into `backend/app/exceptions.py`. Updated router and tests to import the shared domain exceptions from `app.exceptions`.
 - Added global domain exception handlers to `backend/app/main.py` so domain exceptions like `JailNotFoundError`, `ConfigValidationError`, and `ConfigWriteError` map consistently to 404, 400, and 500 responses.
 - Fixed stale activation tracking in `backend/app/routers/jail_config.py` by recording `last_activation` only after a successful jail activation and preventing a failed activation attempt from leaving a stale runtime state record.
+- Fixed infinite re-fetch loop in `frontend/src/hooks/useJailConfigs.ts` by wrapping the `onSuccess` callback in `useCallback` with empty dependencies. The bug occurred because `useListData` includes `onSuccess` in its internal `refresh` function's dependency array; an inline callback created a new reference on each render, causing `refresh` to be recreated, which triggered the `useEffect` again, leading to an unbounded fetch loop. Callers of `useListData` must always wrap `onSuccess` callbacks in `useCallback` to maintain reference stability.