Bug Description

The onboarding wizard auto-populates https://api.moonshot.cn/v1 as the baseUrl when configuring the Moonshot/Kimi provider. For users with API keys created on the international platform (platform.moonshot.ai), this endpoint returns 401 Invalid Authentication — but Clawdbot surfaces zero error output. The model silently fails to respond.

Steps to Reproduce

1. Run clawdbot onboard and configure Moonshot Kimi as a provider
2. Enter a valid API key from platform.moonshot.ai
3. Wizard saves baseUrl as https://api.moonshot.cn/v1 in clawdbot.json
4. Attempt to use the Moonshot model (e.g. as a fallback)
5. Model silently fails — no error in console, no logs, nothing

Expected Behavior

• Wizard should default to https://api.moonshot.ai/v1 (the international endpoint)
• If the endpoint returns 401, Clawdbot should log the error visibly and notify the user
• Ideally: wizard validates the endpoint with a /v1/models call before saving config

Actual Behavior

• api.moonshot.cn/v1 returns 401 Invalid Authentication
• Clawdbot shows no error — complete silence
• User has no way to diagnose the issue without manually curl-testing endpoints

Verification

# .cn endpoint — FAILS (401)
curl -s https://api.moonshot.cn/v1/models -H "Authorization: Bearer $KEY"
# {"error":{"message":"Invalid Authentication","type":"invalid_authentication_error"}}

# .ai endpoint — WORKS (200)
curl -s https://api.moonshot.ai/v1/models -H "Authorization: Bearer $KEY"
# Returns model list successfully

Impact

• 2+ hours of debugging time lost
• User topped up $100 in credits thinking it was a billing/tier issue
• Silent failure makes this nearly impossible to self-diagnose

Suggested Fix

1. Default Moonshot baseUrl to https://api.moonshot.ai/v1
2. Surface HTTP error responses (especially 401) in console/logs
3. Validate provider URL at config time with a lightweight API call

Environment

• Clawdbot: 2026.1.24-3
• OS: macOS
• Node: v24.13.0