Fix getCallerBaggagePairs: resolve userId across all channels

[fpfp100]

Summary

• Port of Fix GetCallerBaggagePairs: resolve userId across all channels Agent365-dotnet#246
• userId baggage was only set from aadObjectId, which is undefined on non-Teams channels and A2A calls
• Added fallback chain: aadObjectId → agenticUserId → from.id
• Added id field to ActivityLike.from type definition

Channel behavior after fix

Field	Teams	Other channels (aadObjectId null)	A2A (user)	A2A (agent)
userId	aadObjectId	from.id	aadObjectId	agenticUserId

Test plan

• Existing tests pass (19/19)
• New test: non-Teams channel — userId falls back to from.id
• New test: A2A — userId falls back to agenticUserId
• New test: precedence — aadObjectId wins when all set

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR updates A365 hosting baggage extraction so user.id can be resolved across non-Teams channels and agent-to-agent (A2A) calls by adding a fallback chain for caller identity, and adds unit tests to validate the new behavior.

Changes:

• Update getCallerBaggagePairs() to resolve user.id via aadObjectId → agenticUserId → from.id.
• Extend the minimal hosting ActivityLike.from type to include an optional id.
• Add unit tests covering non-Teams fallback, A2A fallback, and precedence when multiple identifiers are present.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
test/internal/unit/a365/hosting/turnContextUtils.test.ts	Adds test coverage for new user.id fallback and precedence behavior.
src/a365/hosting/types.ts	Extends ActivityLike.from with an optional id field for structural compatibility with non-Teams activities.
src/a365/hosting/turnContextUtils.ts	Implements the userId fallback chain used to populate OpenTelemetry baggage.

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[hectorhdzg]

@fpfp100 can you fix format/lint issues? we should be able to merge after that