feat(settings): Jira config UI — admin config tab + per-user token in Profile

- backend: add parent_ticket field to JiraConfigOut/JiraConfigUpdate/_JIRA_KEYS
- backend: add get_jira_parent_ticket() helper in jira_service; use it in auto_create_test_issue() to set issue parent
- frontend/api: add jira_token_set to UserMeOut, jira_api_token to UserPreferencesUpdate, and full JiraConfigOut/Update types with getJiraConfig/updateJiraConfig/testJiraConnection functions
- frontend: expand ProfileSection with Jira API token password field (show/hide), token status badge, and account-id field
- frontend: add JiraConfigSection component (admin): enabled toggle, URL, project key, parent ticket, save + test connection
- frontend: add Jira tab (admin-only) with Link2 icon in SettingsPage sidebar

frontend/src/api/settings.ts

@@ -120,6 +120,7 @@ export interface NotificationPreferences {
 export interface UserPreferencesUpdate {
   notification_preferences?: Partial<NotificationPreferences>;
   jira_account_id?: string | null;
+  jira_api_token?: string | null;
 }
 
 export interface UserMeOut {
@@ -133,6 +134,7 @@ export interface UserMeOut {
   last_login: string | null;
   notification_preferences: NotificationPreferences | null;
   jira_account_id: string | null;
+  jira_token_set: boolean;
 }
 
 export async function getMe(): Promise<UserMeOut> {
@@ -145,3 +147,36 @@ export async function updateMyPreferences(payload: UserPreferencesUpdate): Promi
   return data;
 }
 
+// ---------------------------------------------------------------------------
+// Jira system config (admin only)
+// ---------------------------------------------------------------------------
+
+export interface JiraConfigOut {
+  enabled: boolean;
+  url: string;
+  project_key: string;
+  parent_ticket: string;
+}
+
+export interface JiraConfigUpdate {
+  enabled?: boolean;
+  url?: string;
+  project_key?: string;
+  parent_ticket?: string;
+}
+
+export async function getJiraConfig(): Promise<JiraConfigOut> {
+  const { data } = await client.get<JiraConfigOut>("/system/jira-config");
+  return data;
+}
+
+export async function updateJiraConfig(payload: JiraConfigUpdate): Promise<JiraConfigOut> {
+  const { data } = await client.patch<JiraConfigOut>("/system/jira-config", payload);
+  return data;
+}
+
+export async function testJiraConnection(): Promise<{ status: string; connected_as: string; jira_url: string }> {
+  const { data } = await client.post("/system/jira-test");
+  return data;
+}
+