test: stabilize MCP stderr probe timeout

tests/hooks/mcp-health-check.test.js

@@ -568,7 +568,7 @@ async function runTests() {
           CLAUDE_HOOK_EVENT_NAME: 'PreToolUse',
           ECC_MCP_CONFIG_PATH: configPath,
           ECC_MCP_HEALTH_STATE_PATH: statePath,
-          ECC_MCP_HEALTH_TIMEOUT_MS: process.platform === 'win32' ? '1000' : '100'
+          ECC_MCP_HEALTH_TIMEOUT_MS: '1000'
         }
       );