Intent of openSessionLink.test|title=openSessionLink round-trips backend session URI|occurrence=1

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
    
    common/ 2 tests
    
    mocha:v1|namespace=vscode@05c208e9e28d8c1c723fa08f85e2b7a96092e8e5|file=vs/platform/agentHost/test/common/openSessionLink.test|title=openSessionLink carries an optional chat id|occurrence=1 Inherited openSessionLink.ts ×1
    
    mocha:v1|namespace=vscode@05c208e9e28d8c1c723fa08f85e2b7a96092e8e5|file=vs/platform/agentHost/test/common/openSessionLink.test|title=openSessionLink round-trips backend session URI|occurrence=1 Introduced here
    
    node/ 1 test
    
    sessionServerTools.test|title=SessionServerTools send_message targets the default chat / 1 test
    
    mocha:v1|namespace=vscode@05c208e9e28d8c1c723fa08f85e2b7a96092e8e5|file=vs/platform/agentHost/test/node/sessionServerTools.test|title=SessionServerTools send_message targets the default chat / a specific chat, refuses the current chat, and validates|occurrence=1 Inherited sessionServerTools.ts ×3