feat(users): per-user library assignment + themed confirm modal (#222)

Adds Navidrome library assignment to the User Management settings
panel: GET /api/library + PUT /api/user/{id}/library wired through
new Rust commands. UserForm gets a checkbox picker (hidden for
admins, who auto-receive all libraries server-side) with inline
validation. User rows compacted to a single clickable line with
hover highlight; native confirm() replaced by a portal-based
ConfirmModal (theme-aware, ESC/Enter, vertically centered).

Co-authored-by: Psychotoxical <dev@psysonic.app>
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/api/navidromeAdmin.ts

@@ -1,11 +1,17 @@
 import { invoke } from '@tauri-apps/api/core';
 
+export interface NdLibrary {
+  id: number;
+  name: string;
+}
+
 export interface NdUser {
   id: string;
   userName: string;
   name: string;
   email: string;
   isAdmin: boolean;
+  libraryIds: number[];
   lastLoginAt?: string | null;
   createdAt?: string;
   updatedAt?: string;
@@ -25,6 +31,18 @@ export async function ndLogin(
   return invoke<NdLoginResult>('navidrome_login', { serverUrl, username, password });
 }
 
+function extractLibraryIds(o: Record<string, unknown>): number[] {
+  const libs = o.libraries;
+  if (!Array.isArray(libs)) return [];
+  const ids: number[] = [];
+  for (const l of libs) {
+    const id = (l as Record<string, unknown>)?.id;
+    if (typeof id === 'number') ids.push(id);
+    else if (typeof id === 'string' && /^\d+$/.test(id)) ids.push(Number(id));
+  }
+  return ids;
+}
+
 export async function ndListUsers(serverUrl: string, token: string): Promise<NdUser[]> {
   const raw = await invoke<unknown>('nd_list_users', { serverUrl, token });
   if (!Array.isArray(raw)) return [];
@@ -36,6 +54,7 @@ export async function ndListUsers(serverUrl: string, token: string): Promise<NdU
       name: String(o.name ?? ''),
       email: String(o.email ?? ''),
       isAdmin: !!o.isAdmin,
+      libraryIds: extractLibraryIds(o),
       lastLoginAt: (o.lastLoginAt as string | null | undefined) ?? null,
       createdAt: o.createdAt as string | undefined,
       updatedAt: o.updatedAt as string | undefined,
@@ -43,12 +62,35 @@ export async function ndListUsers(serverUrl: string, token: string): Promise<NdU
   });
 }
 
+export async function ndListLibraries(serverUrl: string, token: string): Promise<NdLibrary[]> {
+  const raw = await invoke<unknown>('nd_list_libraries', { serverUrl, token });
+  if (!Array.isArray(raw)) return [];
+  return raw.map(l => {
+    const o = l as Record<string, unknown>;
+    const id = typeof o.id === 'number'
+      ? o.id
+      : typeof o.id === 'string' && /^\d+$/.test(o.id) ? Number(o.id) : 0;
+    return { id, name: String(o.name ?? '') };
+  }).filter(l => l.id > 0);
+}
+
+export async function ndSetUserLibraries(
+  serverUrl: string,
+  token: string,
+  id: string,
+  libraryIds: number[],
+): Promise<void> {
+  await invoke('nd_set_user_libraries', { serverUrl, token, id, libraryIds });
+}
+
 export async function ndCreateUser(
   serverUrl: string,
   token: string,
   data: { userName: string; name: string; email: string; password: string; isAdmin: boolean },
-): Promise<void> {
-  await invoke('nd_create_user', { serverUrl, token, ...data });
+): Promise<{ id: string }> {
+  const raw = await invoke<unknown>('nd_create_user', { serverUrl, token, ...data });
+  const o = (raw as Record<string, unknown> | null) ?? {};
+  return { id: String(o.id ?? '') };
 }
 
 export async function ndUpdateUser(