feat(modelmgr): split Moonshot/Kimi into Global and China presets (#2264)

Adding a Kimi/Moonshot provider failed model scanning out of the box for
CN-region API keys: the single preset defaulted its base URL to the
global endpoint `https://api.moonshot.ai/v1`, but CN-issued keys are only
valid against `https://api.moonshot.cn/v1`, so scanning returned
`401 Invalid Authentication`. Flipping the default would just move the
breakage to international keys, since the base_url field is plain
free-text and either region is equally common.

Instead, offer two clearly labelled presets, mirroring how the Lark
adapter exposes feishu.cn vs larksuite.com:

- `moonshot-chat-completions`   -> "Moonshot / Kimi (Global · api.moonshot.ai)"
- `moonshot-cn-chat-completions` -> "Moonshot / Kimi (China · api.moonshot.cn)"

The existing component name is kept unchanged so provider rows already in
the DB keep resolving; only its display label is clarified. Both presets
keep base_url as a free-text field, so users behind a proxy / one-api
gateway can still enter a custom endpoint. Both carry the same `kimi`
search aliases so either shows up when searching.

Fixes #2232

src/langbot/pkg/provider/modelmgr/requesters/moonshotchatcmpl.yaml

@@ -3,8 +3,8 @@ kind: LLMAPIRequester
 metadata:
   name: moonshot-chat-completions
   label:
-    en_US: Moonshot
+    en_US: Moonshot / Kimi (Global · api.moonshot.ai)
-    zh_Hans: 月之暗面
+    zh_Hans: 月之暗面 / Kimi（国际站 · api.moonshot.ai）
   icon: moonshot.png
 spec:
   litellm_provider: openai

src/langbot/pkg/provider/modelmgr/requesters/moonshotcnchatcmpl.yaml

@@ -0,0 +1,33 @@
+apiVersion: v1
+kind: LLMAPIRequester
+metadata:
+  name: moonshot-cn-chat-completions
+  label:
+    en_US: Moonshot / Kimi (China · api.moonshot.cn)
+    zh_Hans: 月之暗面 / Kimi（国内站 · api.moonshot.cn）
+  icon: moonshot.png
+spec:
+  litellm_provider: openai
+  config:
+  - name: base_url
+    label:
+      en_US: Base URL
+      zh_Hans: 基础 URL
+    type: string
+    required: true
+    default: https://api.moonshot.cn/v1
+  - name: timeout
+    label:
+      en_US: Timeout
+      zh_Hans: 超时时间
+    type: integer
+    required: true
+    default: 120
+  alias: "moonshot Moonshot 月之暗面 月暗 kimi Kimi 月之 暗面 moonshot-v1 k2 cn 国内 国内站"
+  support_type:
+  - llm
+  provider_category: manufacturer
+execution:
+  python:
+    path: ./moonshotchatcmpl.py
+    attr: MoonshotChatCompletions