Stage 7: configuration view — backend service, routers, tests, and frontend

- config_service.py: read/write jail config via asyncio.gather, global
  settings, in-process regex validation, log preview via _read_tail_lines
- server_service.py: read/write server settings, flush logs
- config router: 9 endpoints for jail/global config, regex-test,
  logpath management, log preview
- server router: GET/PUT settings, POST flush-logs
- models/config.py expanded with JailConfig, GlobalConfigUpdate,
  LogPreview* models
- 285 tests pass (68 new), ruff clean, mypy clean (44 files)
- Frontend: types/config.ts, api/config.ts, hooks/useConfig.ts,
  ConfigPage.tsx full implementation (Jails accordion editor,
  Global config, Server settings, Regex Tester with preview)
- Fixed pre-existing frontend lint: JSX.Element → React.JSX.Element
  (10 files), void/promise patterns in useServerStatus + useJails,
  no-misused-spread in client.ts, eslint.config.ts self-excluded

frontend/src/api/config.ts

@@ -0,0 +1,121 @@
+/**
+ * API functions for the configuration and server settings endpoints.
+ */
+
+import { get, post, put } from "./client";
+import { ENDPOINTS } from "./endpoints";
+import type {
+  AddLogPathRequest,
+  GlobalConfig,
+  GlobalConfigUpdate,
+  JailConfigListResponse,
+  JailConfigResponse,
+  JailConfigUpdate,
+  LogPreviewRequest,
+  LogPreviewResponse,
+  RegexTestRequest,
+  RegexTestResponse,
+  ServerSettingsResponse,
+  ServerSettingsUpdate,
+} from "../types/config";
+
+// ---------------------------------------------------------------------------
+// Jail configuration
+// ---------------------------------------------------------------------------
+
+export async function fetchJailConfigs(
+): Promise<JailConfigListResponse> {
+  return get<JailConfigListResponse>(ENDPOINTS.configJails);
+}
+
+export async function fetchJailConfig(
+  name: string
+): Promise<JailConfigResponse> {
+  return get<JailConfigResponse>(ENDPOINTS.configJail(name));
+}
+
+export async function updateJailConfig(
+  name: string,
+  update: JailConfigUpdate
+): Promise<void> {
+  await put<undefined>(ENDPOINTS.configJail(name), update);
+}
+
+// ---------------------------------------------------------------------------
+// Global configuration
+// ---------------------------------------------------------------------------
+
+export async function fetchGlobalConfig(
+): Promise<GlobalConfig> {
+  return get<GlobalConfig>(ENDPOINTS.configGlobal);
+}
+
+export async function updateGlobalConfig(
+  update: GlobalConfigUpdate
+): Promise<void> {
+  await put<undefined>(ENDPOINTS.configGlobal, update);
+}
+
+// ---------------------------------------------------------------------------
+// Reload
+// ---------------------------------------------------------------------------
+
+export async function reloadConfig(
+): Promise<void> {
+  await post<undefined>(ENDPOINTS.configReload, undefined);
+}
+
+// ---------------------------------------------------------------------------
+// Regex tester
+// ---------------------------------------------------------------------------
+
+export async function testRegex(
+  req: RegexTestRequest
+): Promise<RegexTestResponse> {
+  return post<RegexTestResponse>(ENDPOINTS.configRegexTest, req);
+}
+
+// ---------------------------------------------------------------------------
+// Log path management
+// ---------------------------------------------------------------------------
+
+export async function addLogPath(
+  jailName: string,
+  req: AddLogPathRequest
+): Promise<void> {
+  await post<undefined>(ENDPOINTS.configJailLogPath(jailName), req);
+}
+
+// ---------------------------------------------------------------------------
+// Log preview
+// ---------------------------------------------------------------------------
+
+export async function previewLog(
+  req: LogPreviewRequest
+): Promise<LogPreviewResponse> {
+  return post<LogPreviewResponse>(ENDPOINTS.configPreviewLog, req);
+}
+
+// ---------------------------------------------------------------------------
+// Server settings
+// ---------------------------------------------------------------------------
+
+export async function fetchServerSettings(
+): Promise<ServerSettingsResponse> {
+  return get<ServerSettingsResponse>(ENDPOINTS.serverSettings);
+}
+
+export async function updateServerSettings(
+  update: ServerSettingsUpdate
+): Promise<void> {
+  await put<undefined>(ENDPOINTS.serverSettings, update);
+}
+
+export async function flushLogs(
+): Promise<string> {
+  const resp = await post<{ message: string }>(
+    ENDPOINTS.serverFlushLogs,
+    undefined,
+  );
+  return resp.message;
+}