implementation for CalendarClient V3

[bmerkle]

• replaced empty dummy implementation of calendar with working version (based on V2 behaviour)
• enhanced calendar client login with better authentication and error handling
• fixed some arguments (e.g. passing of dates/search strings(

[Copilot]

Pull request overview

This PR wires up the Calendar V3 agent to a real MS Graph-backed CalendarClient, adds proper login/logout commands, and improves Graph authentication behavior including silent login and clearer failure modes.

Changes:

• Implemented a fully functional CalendarActionHandlerV3 that uses CalendarClient to schedule events, find events (by description/date), add participants, and list today’s/this week’s events, returning rich HTML display results.
• Enhanced GraphClient’s device-code login flow to distinguish silent vs interactive authentication, use cached tokens when available, and surface clearer error conditions when credentials are missing or expired.
• Updated CalendarClient to attempt a silent login on construction and hook into GraphClient’s connected/disconnected events to manage the calendar indexing sync thread.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 5 comments.

File	Description
ts/packages/agents/calendar/src/calendarActionHandlerV3.ts	Replaces the previous stubbed V3 handler with a Graph-integrated implementation plus login/logout command handlers and HTML formatting helpers.
ts/packages/agents/agentUtils/graphUtils/src/graphClient.ts	Refines device-code authentication options and error handling for silent vs interactive MS Graph login.
ts/packages/agents/agentUtils/graphUtils/src/calendarClient.ts	Adds constructor-time silent login attempt and keeps the calendar sync thread wired to Graph connection lifecycle.

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[robgruen]

This is great, thank you! FYI @steveluc , since you're working on updated calendar stuff.

[robgruen]

@bmerkle , getting a build issue, can you investigate please: