Intent of copilotAgent.ts ×2

All 3 exact tests in this concept. Every test is marked by where it enters the hierarchy.

mocha:v1|namespace=vscode@05c208e9e28d8c1c723fa08f85e2b7a96092e8e5|file=vs/ 3 tests
- platform/ 3 tests
  - agentHost/ 3 tests
    
    test/ 3 tests
    
    node/ 3 tests
    
    mocha:v1|namespace=vscode@05c208e9e28d8c1c723fa08f85e2b7a96092e8e5|file=vs/platform/agentHost/test/node/copilotAgent.test|title=CopilotAgent _resumeSession dedup shutdown during resume cancels the in-flight resume|occurrence=1 Inherited copilotAgent.test|title=CopilotAgent _resumeSession dedup shutdown during resume cancels the in-flight resume|occurrence=1
    
    mocha:v1|namespace=vscode@05c208e9e28d8c1c723fa08f85e2b7a96092e8e5|file=vs/platform/agentHost/test/node/copilotAgent.test|title=CopilotAgent _resumeSession fallback does not restore a persisted custom agent that is absent from the current plugin snapshot|occurrence=1 Inherited copilotAgent.ts ×1
    
    mocha:v1|namespace=vscode@05c208e9e28d8c1c723fa08f85e2b7a96092e8e5|file=vs/platform/agentHost/test/node/copilotAgent.test|title=CopilotAgent _resumeSession fallback retries resume without a custom agent when the SDK reports the stored agent is missing|occurrence=1 Inherited copilotSessionLauncher.ts ×3