Add TeamsChannelAccount and update member/meeting APIs to use it

[Copilot]

Port of teams.ts#409. Teams uses different account schemas depending on the API—conversation.members and meeting participant APIs return additional Teams-specific fields that the base Account type doesn't capture.

Changes

• New TeamsChannelAccount class extending Account with:

  • GivenName, Surname, Email, UserPrincipalName, TenantId

• Updated return types:

  • MemberClient.GetAsync() / GetByIdAsync() → TeamsChannelAccount
  • Meeting.Organizer → TeamsChannelAccount
  • MeetingParticipant.User → TeamsChannelAccount
  • MeetingParticipantJoinActivity / MeetingParticipantLeaveActivity member user → TeamsChannelAccount

Usage

var members = await memberClient.GetAsync(conversationId);
// Now returns List<TeamsChannelAccount> with access to:
var email = members[0].Email;
var upn = members[0].UserPrincipalName;
var givenName = members[0].GivenName;

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• token.botframework.com
  • Triggering command: /usr/share/dotnet/dotnet /usr/share/dotnet/dotnet exec --runtimeconfig /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net9.0/Microsoft.Teams.Apps.Tests.runtimeconfig.json --depsfile /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net9.0/Microsoft.Teams.Apps.Tests.deps.json /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net9.0/testhost.dll --port 35425 --endpoint 127.0.0.1:035425 --role client --parentprocessid 4684 --telemetryoptedin false (dns block)
  • Triggering command: /usr/share/dotnet/dotnet /usr/share/dotnet/dotnet exec --runtimeconfig /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net9.0/Microsoft.Teams.Apps.Tests.runtimeconfig.json --depsfile /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net9.0/Microsoft.Teams.Apps.Tests.deps.json /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net9.0/testhost.dll --port 38091 --endpoint 127.0.0.1:038091 --role client --parentprocessid 5037 --telemetryoptedin false (dns block)
  • Triggering command: /usr/share/dotnet/dotnet /usr/share/dotnet/dotnet exec --runtimeconfig /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net9.0/Microsoft.Teams.Apps.Tests.runtimeconfig.json --depsfile /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net9.0/Microsoft.Teams.Apps.Tests.deps.json /home/REDACTED/work/teams.net/teams.net/Tests/Microsoft.Teams.Apps.Tests/bin/Debug/net9.0/testhost.dll --port 41695 --endpoint 127.0.0.1:041695 --role client --parentprocessid 6893 --telemetryoptedin false (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

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