feat(api): 统一公开接口为 /api/v1 前缀

将通用生成、Gemini、可灵、火山、健康检查与 OpenAPI 的推荐入口统一到 /api/v1，并保留历史路径作为兼容别名。同步更新代理配置、接入文档、接口清单和前缀回归测试。\n\n验证：go vet ./...；go test ./...；pnpm openapi；pnpm lint；pnpm test；pnpm build；公开 OpenAPI 71 个方法与接口清单机器比对一致。

docker/nginx.conf

@@ -33,6 +33,10 @@ server {
     return 404;
   }
 
+  location = /api/v1/metrics {
+    return 404;
+  }
+
   location = /gateway-api/api/v1/auth/login {
     proxy_http_version 1.1;
     proxy_set_header Host $host;
@@ -47,6 +51,35 @@ server {
     proxy_pass http://api:8088/api/v1/auth/login;
   }
 
+  location = /api/v1/auth/login {
+    proxy_http_version 1.1;
+    proxy_set_header Host $host;
+    proxy_set_header X-Real-IP $remote_addr;
+    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+    proxy_set_header X-Forwarded-Proto $scheme;
+    proxy_set_header Connection "";
+    proxy_connect_timeout 3s;
+    proxy_read_timeout 15s;
+    proxy_send_timeout 15s;
+    proxy_redirect off;
+    proxy_pass http://api:8088;
+  }
+
+  # Canonical public API. Keep the request URI so /api/v1 reaches the
+  # versioned handlers without another prefix rewrite.
+  location ^~ /api/v1/ {
+    proxy_http_version 1.1;
+    proxy_set_header Host $host;
+    proxy_set_header X-Real-IP $remote_addr;
+    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+    proxy_set_header X-Forwarded-Proto $scheme;
+    proxy_set_header Connection "";
+    proxy_buffering off;
+    proxy_read_timeout 3600s;
+    proxy_send_timeout 3600s;
+    proxy_pass http://api:8088;
+  }
+
   location /gateway-api/ {
     proxy_http_version 1.1;
     proxy_set_header Host $host;