fix(config): align default.yaml with server schema

src/cli/doctor.ts

@@ -71,6 +71,30 @@ const checkConfigValidates: Check = async (ctx) => {
   }
 };
 
+const checkDeprecatedConfigKeys: Check = async (ctx) => {
+  if (!existsSync(ctx.configPath)) {
+    return { status: 'skip', label: 'Config deprecated keys', detail: '(no config file)' };
+  }
+
+  try {
+    const raw = readFileSync(ctx.configPath, 'utf-8');
+    const parsed = parse(raw) as any;
+    const tailscaleOnly = Boolean(parsed?.server && typeof parsed.server === 'object' && 'tailscale_only' in parsed.server);
+
+    if (tailscaleOnly) {
+      return {
+        status: 'warn',
+        label: 'Config deprecated keys',
+        detail: 'server.tailscale_only is deprecated/ignored; use server.tailscale.* + server.localhost instead',
+      };
+    }
+
+    return { status: 'pass', label: 'Config deprecated keys' };
+  } catch {
+    return { status: 'skip', label: 'Config deprecated keys', detail: '(could not read/parse config)' };
+  }
+};
+
 const checkEnvVars: Check = async (ctx) => {
   if (!existsSync(ctx.configPath)) {
     return { status: 'skip', label: 'Env vars resolved', detail: '(no config file)' };
@@ -492,6 +516,7 @@ const allChecks: Check[] = [
   checkConfigExists,
   checkOverlayExists,
   checkConfigParses,
+  checkDeprecatedConfigKeys,
   checkConfigValidates,
   checkEnvVars,
   checkDataDir,