Cannot test latency to a single node

[xmh0511]

It appears we've lost an API that tests latency to a single node. Single-node latency test doesn't work.

Another issue is that the current logic for testing all nodes is not the same as Mihomo's; Mihomo only responds with the result when all nodes' latencies are tested. However, it appears that clash-rs directly responds without waiting.

See the video for what the issue means

QQ20260511-113527.mp4

API

/proxies/${encodeURIComponent(name)}/delay

https://github.com/libnyanpasu/clash-nyanpasu/blob/main/frontend/interface/src/service/clash-api.ts#L126

[ibigbug]

the current proxy latency logic:

1. plain proxy - returned by proxy list endpiont, these are individual proxies that can be tested via the proxy/{name}/latency endpoint
2. provider proxies - are solely manged by provider so fetching and latency test can be done only via proxy provider endpoints
3. group latency test - can be done via either proxy/{name}/latency where group and plain proxies are auto demuxed tested with their regarding behavior

[xmh0511]

the current proxy latency logic:

1. plain proxy - returned by proxy list endpiont, these are individual proxies that can be tested via the proxy/{name}/latency endpoint

2. provider proxies - are solely manged by provider so fetching and latency test can be done only via proxy provider endpoints

3. group latency test - can be done via either proxy/{name}/latency where group and plain proxies are auto demuxed tested with their regarding behavior

However, as shown in the video, the latency test doesn't work(including the test of the latency of the group).