feat: bootstrap MediaStationGo (Go + React rewrite of MediaStation)

Adopt the cropflre/nowen-video tech stack and rebuild the project from
scratch:

  - Backend: Go 1.25 + Gin + GORM + SQLite (WAL) + JWT + WebSocket hub.
    Layered packages config / database / model / repository / service /
    middleware / handler. Default admin (admin/admin123) seeded on first
    run; /api routes for auth, libraries, media, stream and admin
    panels. WebSocket scan-progress events at /api/ws.
  - Frontend: React 18 + Vite 5 + Tailwind 3.4 + Zustand + axios +
    react-router 6 + lucide-react + framer-motion + hls.js. Pages for
    Login / Home / Library / Search / MediaDetail / Player / Admin
    (Library, Users, Settings tabs).
  - Distribution: multi-arch Dockerfile (frontend -> backend -> Alpine
    runtime), docker-compose.yml, GitHub Actions for CI and GHCR
    publish, Makefile, env-prefixed config (MEDIASTATION_*).
  - Docs: README, CONTRIBUTING, .env.example, config.example.yaml.

Backend builds, vets and tests pass. Frontend builds via tsc -b && vite
build (250 kB JS / 16 kB CSS, gzipped 84 / 4 kB).

web/src/api/library.ts

@@ -0,0 +1,35 @@
+import { api } from './client'
+import type { Library, Media, ScanResult } from '../types'
+
+export interface MediaPage {
+  items: Media[]
+  total: number
+  page: number
+  page_size: number
+}
+
+export const libraryAPI = {
+  list: () => api.get<Library[]>('/libraries').then((r) => r.data),
+
+  create: (name: string, path: string, type: string) =>
+    api.post<Library>('/libraries', { name, path, type }).then((r) => r.data),
+
+  remove: (id: string) => api.delete(`/libraries/${id}`).then((r) => r.data),
+
+  scan: (id: string) =>
+    api.post<ScanResult>(`/libraries/${id}/scan`).then((r) => r.data),
+
+  listMedia: (id: string, page = 1, pageSize = 50) =>
+    api
+      .get<MediaPage>(`/libraries/${id}/media`, {
+        params: { page, page_size: pageSize },
+      })
+      .then((r) => r.data),
+}
+
+export const mediaAPI = {
+  search: (q: string, limit = 50) =>
+    api.get<{ items: Media[] }>('/media', { params: { q, limit } }).then((r) => r.data),
+
+  get: (id: string) => api.get<Media>(`/media/${id}`).then((r) => r.data),
+}