refactor(config): separate base URL from API URL for CLI usage

Add signUrl property to config for CLI sign URL without /api/v1 suffix.
Update CLIGuidePage to use config.signUrl instead of hardcoded URL.
Update .env.example and add .swarm/ to .gitignore.

src/pages/user/CLIGuidePage.tsx

@@ -6,8 +6,7 @@ import {
   CollapsibleContent,
   CollapsibleTrigger,
 } from "@/components/ui/collapsible";
-
-const SIGN_URL = "https://api.secuird.tech";
+import { config } from "@/config";
 
 // ── Code block with copy button ────────────────────────────────────────────────
 function CodeBlock({ code }: { code: string }) {
@@ -112,7 +111,7 @@ export default function CLIGuidePage() {
           </Step>
 
           <Step n={3} title="Set your server URL">
-            <CodeBlock code={`echo 'SIGN_URL=${SIGN_URL}' > ~/.secuird/.env`} />
+            <CodeBlock code={`echo 'SIGN_URL=${config.signUrl}' > ~/.secuird/.env`} />
           </Step>
 
           <Step n={4} title="Register your SSH key (once)">