docs(api): mark collection responses nullable (#6430)

* docs(api): mark collection responses nullable

Describe allLinks and panel log response objects as nullable string arrays so generated clients accept the existing nil-slice wire format. Pin both schemas with buildSpec regression assertions and regenerate the OpenAPI copies.

* docs(api): include nullable Xray log responses

Allow generated response arrays to opt into nullability while retaining their schema references and Go-derived examples. Apply this to Xray logs, whose nil slices already serialize as null, and pin the schema and example through buildSpec.

frontend/src/pages/api-docs/endpoints.ts

@@ -46,6 +46,7 @@ export interface Endpoint {
   bodyRequiredOneOf?: string[];
   responseSchema?: string;
   responseSchemaArray?: boolean;
+  responseSchemaArrayNullable?: boolean;
   responseObjectSchema?: Record<string, unknown>;
   responses?: Record<string, Record<string, unknown>>;
   security?: readonly Record<string, readonly string[]>[];
@@ -265,6 +266,7 @@ export const sections: readonly Section[] = [
       {
         method: 'GET',
         path: '/panel/api/inbounds/allLinks',
+        responseObjectSchema: { type: 'array', nullable: true, items: { type: 'string' } },
         summary:
           'Return every protocol URL (vless://, vmess://, trojan://, ss://, hysteria://, mtproto) across all inbounds and all of their clients. Links are rendered through the subscription engine, so the configured remark template (name-only display part) is applied per client — the same output the client info/QR pages use. Protocols without a URL form (socks, http, mixed, wireguard, dokodemo, tunnel) contribute nothing. Used by the panel’s "Export all inbound links" action.',
         response:
@@ -709,7 +711,7 @@ export const sections: readonly Section[] = [
           },
         ],
         body: 'level=info&syslog=false',
-        responseObjectSchema: { type: 'array', items: { type: 'string' } },
+        responseObjectSchema: { type: 'array', nullable: true, items: { type: 'string' } },
         response:
           '{\n  "success": true,\n  "obj": [\n    "2025/01/01 12:00:00 [INFO] Server started",\n    "2025/01/01 12:00:01 [INFO] Xray is running"\n  ]\n}',
       },
@@ -751,6 +753,7 @@ export const sections: readonly Section[] = [
         body: 'filter=error&showDirect=false&showBlocked=true&showProxy=true',
         responseSchema: 'LogEntry',
         responseSchemaArray: true,
+        responseSchemaArrayNullable: true,
       },
       {
         method: 'POST',