* feat(provider): add LiteLLM as an OpenAI-compatible provider
* docs: use revive-compliant comment for ProviderLiteLLM const
* fix(provider): stop defaulting LiteLLM to localhost under SSRF
The catalog URL localhost:4000 is blocked by default SSRF and does not
match DetectProvider, so UI/CLI could neither save nor auto-detect it.
Use a placeholder host, keep thinking aligned with generic, and sync
ModelSource across types, Swagger, and docs.
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Co-authored-by: wizardchen <wizardchen@tencent.com>