[giannik]

Fixes #274

A cascaded realtime session now keeps a reply's tool calls and their results in its history, with the reply's text,
so the next turn knows what was looked up.

Changes

• CascadedRealtimeSession.RunTurnAsync keeps every update the chat leg streams for a reply, and adds the reply's
  messages to the history in place of its text alone: the tool calls, their results, then the text.
  • This happens on completion and on interruption alike: what was said before an interruption stays, as before, and
    so does what was looked up for it.
  • A reply marked ExcludeFromConversation still stays out of the history.
• A call an interruption left unanswered is left out. A reply cancelled between asking for a tool and getting its
  answer leaves a FunctionCallContent with no FunctionResultContent. Providers that pair each call with its result
  (Anthropic among them) refuse a conversation holding one.
• Docs:
  • core/realtime-voice.md, the chat leg: what the history keeps;
  • a changelog entry under cascaded realtime deployments.

Tests

In CascadedRealtimeSessionTests:

• Session_KeepsTheToolCallsAndTheirResultsInHistoryForTheNextTurn: the second turn's request holds the call and
  its result, in order, before the answer built on them.
• Session_LeavesOutAToolCallTheInterruptionLeftUnanswered: a reply interrupted after its call leaves no
  FunctionCallContent in the next request.

The fake chat client can now emit any update, and can hold only its first reply. The existing tests use it as before.

On our fork, the realtime tests pass (189), and so does the full test project, except the 2 known failures under a
Greek locale (EmbeddedResourceAIProfileTemplateProviderTests, OpenXmlIngestionDocumentReaderTests), which fail
the same way without this change.

Verified on a live call

The call ran through CrestApps.OrchardCore's voice agent on Telnyx, on a cascade of Deepgram nova-3,
claude-haiku-5-5 and ElevenLabs eleven_flash_v2_5, with a booking profile.

• Before: the model retracted a correct availability answer on the next turn ("I didn't actually check our
  booking calendar").
• After:
  • "Next Tuesday afternoon" led to listCalendars and getAvailableSlots, then a choice of dates.
  • "Give me the first available slot" was answered from the slots already found, without asking the calendar again.
  • The name and email were confirmed, then bookAppointment ran, and the booking was confirmed.

🤖 Generated with Claude Code

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