feat: implement user authentication and license management system

- Added schema for users, licenses, and license hostnames in the database.
- Created storage utility for reading and writing JSON files.
- Developed user service for user registration, authentication, and retrieval.
- Implemented authentication middleware to protect routes.
- Built LicenseCard component to display license details.
- Created SiteNav component for navigation with user authentication status.
- Established AuthContext for managing authentication state and actions.
- Developed Home page to display available plugins.
- Created LicenseManager page for managing licenses with forms for creation and verification.
- Implemented PluginDetail page to show detailed information about a specific plugin.
- Added utility functions for date formatting.

server/lib/config.js

@@ -0,0 +1,29 @@
+import path from "path";
+import { fileURLToPath } from "url";
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
+const serverDir = path.resolve(__dirname, "..");
+const rootDir = path.resolve(serverDir, "..");
+
+export const PATHS = {
+    serverDir,
+    rootDir,
+    distDir: path.join(rootDir, "dist"),
+    reposFile: path.join(serverDir, "repos.json")
+};
+
+export const PORT = process.env.PORT || 3001;
+export const HOST = process.env.HOST || "::";
+export const CACHE_TTL_MS = Number(process.env.CACHE_TTL_MS || 10 * 60 * 1000);
+
+export const DB_CONFIG = {
+    host: process.env.DB_HOST || "127.0.0.1",
+    port: Number(process.env.DB_PORT || 3306),
+    user: process.env.DB_USER || "root",
+    password: process.env.DB_PASSWORD || "",
+    database: process.env.DB_NAME || "siti_plugin_repo"
+};
+
+export const JWT_SECRET = process.env.JWT_SECRET || "change-me-in-production";
+export const JWT_EXPIRES_IN = process.env.JWT_EXPIRES_IN || "7d";