feat: rename WHM→NixServer, cPanel→NixClient, bump v0.2.0

- Rename frontend workspaces: whm/ → nixserver/, cpanel/ → nixclient/
- Rename server route dirs: routes/whm/ → routes/nixserver/, routes/cpanel/ → routes/nixclient/
- Update all API prefixes: /api/whm → /api/nixserver, /api/cpanel → /api/nixclient
- Rename env vars: WHM_PORT → NIXSERVER_PORT, CPANEL_PORT → NIXCLIENT_PORT
- Update config properties: whmPort → nixserverPort, cpanelPort → nixclientPort
- Update all UI labels, login pages, sidebar branding, and error messages
- Update installer and update scripts to match new names
- Add cpanel email route (missing from initial scaffold)
- Add .gitattributes to enforce LF line endings
- Bump version to 0.2.0 across all package.json files

server/src/routes/auth/index.ts

@@ -37,7 +37,7 @@ function signTokens(
 export default async function authRoutes(fastify: FastifyInstance) {
   /**
    * POST /api/auth/login
-   * Login for admin, reseller, or cPanel user.
+   * Login for admin, reseller, or NixClient user.
    * Body: { username, password }
    * Returns: { accessToken, refreshToken, role, user }
    */
@@ -111,7 +111,7 @@ export default async function authRoutes(fastify: FastifyInstance) {
       })
     }
 
-    // Try hosting account (cPanel user)
+    // Try hosting account (NixClient user)
     const account = await prisma.account.findUnique({ where: { username } })
     if (account) {
       if (account.status !== 'active') {