Anna.zhdan/protcol update

[anna239]

• session/close
• additionalDirectories
• nes

[egor-baranov]

The RFD for additional directories also explicitly extends session/list by adding ListSessionsRequest.additionalDirectories and defines exact-match filtering against the authoritative ordered additional-root list returned in SessionInfo.additionalDirectories.

In the current implementation, additionalDirectories was added to lifecycle requests and SessionInfo, but ListSessionsRequest, Client.listSessions(), and AgentSupport.listSessions() are still cwd-only. That means the SDK cannot express the required session/list filter and cannot fully support the recovery flow described in the RFD for preserving/reconstructing additional roots across load/resume.

That's not critical for overall additionalDirectories functionality, just required for consistency with RFD and better session observability.

[anna239]

@egor-baranov thank you for noticing, fix is here #89