Intent of forwardedChatError.ts ×1

All 5 exact tests in this concept. Every test is marked by where it enters the hierarchy.

mocha:v1|namespace=vscode@05c208e9e28d8c1c723fa08f85e2b7a96092e8e5|file=vs/ 5 tests
- platform/ 5 tests
  - agentHost/ 5 tests
    
    test/ 5 tests
    
    node/ 5 tests
    
    mocha:v1|namespace=vscode@05c208e9e28d8c1c723fa08f85e2b7a96092e8e5|file=vs/platform/agentHost/test/node/claudeProxyService.test|title=ClaudeProxyService Streaming mid-stream CopilotApiError → SSE error frame, then end, no message_stop after|occurrence=1 Inherited claudeProxyService.ts ×1
    
    mocha:v1|namespace=vscode@05c208e9e28d8c1c723fa08f85e2b7a96092e8e5|file=vs/platform/agentHost/test/node/claudeProxyService.test|title=ClaudeProxyService Streaming pre-stream CopilotApiError with streaming sentinel coerces to 502 but preserves envelope|occurrence=1 Inherited claudeProxyService.test|title=ClaudeProxyService Streaming pre-stream CopilotApiError with streaming sentinel coerces to 502 but preserves envelope|occurrence=1
    
    mocha:v1|namespace=vscode@05c208e9e28d8c1c723fa08f85e2b7a96092e8e5|file=vs/platform/agentHost/test/node/forwardedChatError.test|title=forwardedChatError buildForwardedChatError maps HTTP status to the matching fetch type|occurrence=1 Inherited forwardedChatError.ts ×2
    
    mocha:v1|namespace=vscode@05c208e9e28d8c1c723fa08f85e2b7a96092e8e5|file=vs/platform/agentHost/test/node/forwardedChatError.test|title=forwardedChatError buildForwardedChatError mid-stream streaming sentinel maps to failed|occurrence=1 Introduced here
    
    mocha:v1|namespace=vscode@05c208e9e28d8c1c723fa08f85e2b7a96092e8e5|file=vs/platform/agentHost/test/node/forwardedChatError.test|title=forwardedChatError buildForwardedChatError null request id becomes empty string|occurrence=1 Introduced here