[SignalR] Add serverless auth-refresh binding and ServerlessHub refresh APIs

[Shiying Chen (MoChilia)]

Issue describing the changes in this PR

Summary

Adds serverless authentication-refresh support to the .NET isolated SignalR worker extension: a [SignalRRefreshInput] binding and ServerlessHub refresh APIs to extend a live connection's auth (and claims) without reconnecting.

Changes

• New [SignalRRefreshInput] input binding (maps to the host signalRRefresh binding); binds a SignalRConnectionInfo with the refreshed access token and TokenLifetimeSeconds.
• ServerlessHub.RefreshConnectionAuthenticationAsync / GetConnectionClaimsAsync for in-worker use by isolated hubs.
• SignalRConnectionInfo.TokenLifetimeSeconds added (advertised at negotiate for refresh scheduling).
• Bumped Management SDK and WebJobs extension dependencies.

Dependency

[DO NOT MERGE] Requires a Microsoft.Azure.SignalR.Management version exposing RefreshConnectionAuthenticationAsync / GetConnectionClaimsAsync, and the new WebJobs SignalR extension.

Pull request checklist

• My changes do not require documentation changes
  • Otherwise: Documentation issue linked to PR
• My changes should not be added to the release notes for the next release
  • Otherwise: I've added my notes to release_notes.md
• My changes do not need to be backported to a previous version
  • Otherwise: Backport tracked by issue/PR #issue_or_pr
• I have added all required tests (Unit tests, E2E tests)

Additional information

Additional PR information

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