fix: buffer MCP server stderr instead of logging every line as error#1346
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MCP servers use stderr for all logging (stdout is reserved for JSON-RPC), so every [INFO], [DEBUG], and Warning: line was being logged at error level in real time. Align with Claude Code's approach: buffer stderr silently (64MB cap) and only dump it on connection failure (error level) or successful connection (debug level).
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MCP servers use stderr for all logging (stdout is reserved for
JSON-RPC), so every [INFO], [DEBUG], and Warning: line was being
logged at error level in real time. Align with Claude Code's approach:
buffer stderr silently (64MB cap) and only dump it on connection
failure (error level) or successful connection (debug level).