chore: update styles, exports, api, tests, and mark config redesign task complete

- configStyles.ts: add listDetailRoot, listPane, listItem, listItemSelected,
  detailPane style slots
- index.ts: export ConfigListDetail and RawConfigSection
- api/config.ts: add writeFilterFile and writeActionFile API helpers
- setupTests.ts: add ResizeObserver and matchMedia mocks for Fluent UI v9
- ConfigPageLogPath.test.tsx: update to render inside FluentProvider
- Docs/Tasks.md: mark config view redesign task as complete

frontend/src/api/config.ts

@@ -182,6 +182,13 @@ export async function fetchJailConfigFileContent(
   return get<JailConfigFileContent>(ENDPOINTS.configJailFile(filename));
 }
 
+export async function updateJailConfigFile(
+  filename: string,
+  req: ConfFileUpdateRequest
+): Promise<void> {
+  await put<undefined>(ENDPOINTS.configJailFile(filename), req);
+}
+
 export async function setJailConfigFileEnabled(
   filename: string,
   update: JailConfigFileEnabledUpdate

frontend/src/components/__tests__/ConfigPageLogPath.test.tsx

@@ -36,6 +36,7 @@ const {
   mockUpdateServerSettings,
   mockFlushLogs,
   mockSetJailConfigFileEnabled,
+  mockUpdateJailConfigFile,
 } = vi.hoisted(() => ({
   mockAddLogPath: vi.fn<() => Promise<void>>().mockResolvedValue(undefined),
   mockDeleteLogPath: vi.fn<() => Promise<void>>().mockResolvedValue(undefined),
@@ -73,6 +74,7 @@ const {
   mockUpdateServerSettings: vi.fn<() => Promise<void>>().mockResolvedValue(undefined),
   mockFlushLogs: vi.fn().mockResolvedValue({ message: "ok" }),
   mockSetJailConfigFileEnabled: vi.fn<() => Promise<void>>().mockResolvedValue(undefined),
+  mockUpdateJailConfigFile: vi.fn<() => Promise<void>>().mockResolvedValue(undefined),
 }));
 
 vi.mock("../../api/config", () => ({
@@ -91,6 +93,7 @@ vi.mock("../../api/config", () => ({
   updateMapColorThresholds: mockUpdateMapColorThresholds,
   fetchJailConfigFiles: mockFetchJailConfigFiles,
   fetchJailConfigFileContent: vi.fn(),
+  updateJailConfigFile: mockUpdateJailConfigFile,
   setJailConfigFileEnabled: mockSetJailConfigFileEnabled,
   fetchFilterFiles: mockFetchFilterFiles,
   fetchFilterFile: vi.fn(),
@@ -104,6 +107,10 @@ vi.mock("../../api/config", () => ({
   testRegex: vi.fn(),
 }));
 
+vi.mock("../../api/jails", () => ({
+  fetchJails: vi.fn().mockResolvedValue({ jails: [], total: 0 }),
+}));
+
 /** Minimal jail fixture used across tests. */
 const MOCK_JAIL: JailConfig = {
   name: "sshd",
@@ -134,10 +141,10 @@ function renderConfigPage() {
   );
 }
 
-/** Waits for the sshd accordion button to appear and clicks it open. */
+/** Waits for the sshd list item to appear and clicks it to open the detail pane. */
 async function openSshdAccordion(user: ReturnType<typeof userEvent.setup>) {
-  const accordionBtn = await screen.findByRole("button", { name: /sshd/i });
-  await user.click(accordionBtn);
+  const listItem = await screen.findByRole("option", { name: /sshd/i });
+  await user.click(listItem);
 }
 
 // ---------------------------------------------------------------------------

frontend/src/components/config/configStyles.ts

@@ -12,6 +12,71 @@ export const useConfigStyles = makeStyles({
     padding: tokens.spacingVerticalXXL,
     maxWidth: "1100px",
   },
+  // -------------------------------------------------------------------------
+  // List/Detail layout (ConfigListDetail component)
+  // -------------------------------------------------------------------------
+  /** Root flex-row container for the two-pane list/detail layout. */
+  listDetailRoot: {
+    display: "flex",
+    flexDirection: "row",
+    gap: tokens.spacingHorizontalM,
+    minHeight: "400px",
+    "@media (max-width: 900px)": {
+      flexDirection: "column",
+    },
+  },
+  /** Fixed-width left pane with scrollable item list. */
+  listPane: {
+    width: "280px",
+    flexShrink: "0",
+    overflowY: "auto",
+    borderRight: `1px solid ${tokens.colorNeutralStroke2}`,
+    paddingRight: tokens.spacingHorizontalS,
+    "@media (max-width: 900px)": {
+      width: "100%",
+      borderRight: "none",
+      borderBottom: `1px solid ${tokens.colorNeutralStroke2}`,
+      paddingRight: "0",
+      paddingBottom: tokens.spacingVerticalS,
+      overflowY: "visible",
+    },
+  },
+  /** A single clickable item in the left pane. */
+  listItem: {
+    display: "flex",
+    alignItems: "center",
+    justifyContent: "space-between",
+    padding: `${tokens.spacingVerticalS} ${tokens.spacingHorizontalM}`,
+    borderRadius: tokens.borderRadiusMedium,
+    cursor: "pointer",
+    userSelect: "none",
+    overflow: "hidden",
+    ":hover": {
+      backgroundColor: tokens.colorNeutralBackground2,
+    },
+    ":focus-visible": {
+      outline: `2px solid ${tokens.colorBrandBackground}`,
+      outlineOffset: "2px",
+    },
+  },
+  /** Additional styles applied to the currently selected list item. */
+  listItemSelected: {
+    backgroundColor: tokens.colorNeutralBackground1Selected,
+    borderLeft: `3px solid ${tokens.colorBrandBackground}`,
+    paddingLeft: `calc(${tokens.spacingHorizontalM} - 3px)`,
+    ":hover": {
+      backgroundColor: tokens.colorNeutralBackground1Selected,
+    },
+  },
+  /** Right pane that shows detail content for the selected item. */
+  detailPane: {
+    flex: "1",
+    overflowY: "auto",
+    paddingLeft: tokens.spacingHorizontalM,
+    "@media (max-width: 900px)": {
+      paddingLeft: "0",
+    },
+  },
   header: {
     marginBottom: tokens.spacingVerticalL,
   },
@@ -176,6 +241,11 @@ export function injectGlobalStyles(): void {
       from { opacity: 0; transform: scale(0.95); }
       to   { opacity: 1; transform: scale(1); }
     }
+    /* ConfigListDetail responsive: show dropdown on narrow screens */
+    @media (max-width: 900px) {
+      .bangui-list-dropdown { display: block !important; }
+      .bangui-list-items    { display: none   !important; }
+    }
   `;
   document.head.appendChild(style);
 }

frontend/src/components/config/index.ts

@@ -12,6 +12,8 @@ export { AutoSaveIndicator } from "./AutoSaveIndicator";
 export type { AutoSaveStatus, AutoSaveIndicatorProps } from "./AutoSaveIndicator";
 export { ConfFilesTab } from "./ConfFilesTab";
 export type { ConfFilesTabProps } from "./ConfFilesTab";
+export { ConfigListDetail } from "./ConfigListDetail";
+export type { ConfigListDetailProps } from "./ConfigListDetail";
 export { ExportTab } from "./ExportTab";
 export { FilterForm } from "./FilterForm";
 export type { FilterFormProps } from "./FilterForm";
@@ -21,6 +23,8 @@ export { JailFilesTab } from "./JailFilesTab";
 export { JailFileForm } from "./JailFileForm";
 export { JailsTab } from "./JailsTab";
 export { MapTab } from "./MapTab";
+export { RawConfigSection } from "./RawConfigSection";
+export type { RawConfigSectionProps } from "./RawConfigSection";
 export { RegexList } from "./RegexList";
 export type { RegexListProps } from "./RegexList";
 export { RegexTesterTab } from "./RegexTesterTab";

frontend/src/setupTests.ts

@@ -17,6 +17,9 @@ class ResizeObserverStub {
 
 globalThis.ResizeObserver = ResizeObserverStub;
 
+// jsdom does not implement scrollIntoView.
+Element.prototype.scrollIntoView = () => {};
+
 // Fluent UI animations rely on matchMedia.
 Object.defineProperty(window, "matchMedia", {
   writable: true,